Glass sheet including divalent IONS of europium or trivalent IONS of cerium or both and solar panel including the glass sheet

Abstract

A glass sheet including: a silica glass composition comprising Eu2+ ion and / or Ce3+ ions. The glass sheet exhibits, at a thickness of 0.7 mm, (i) less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm, (ii) less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm, (iii) greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm, and (iv) a photoluminescence quantum yield of greater than 50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm. A solar panel including (a) one or more photovoltaic cells; and (b) the glass sheet as a cover over the one or more photovoltaic cells.

Description

Attorney Docket No. SP24-152PCT GLASS SHEET INCLUDING DIVALENT IONS OF EUROPIUM OR TRIVALENT IONS OF CERIUM OR BOTH AND SOLAR PANEL INCLUDING THE GLASS SHEET CROSS-REFERENCETORELATEDAPPLICATIONS

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. ProvisionalApplication No.63 / 688,560 filed August 29, 2024, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present invention generally relates to a glass sheet that includes photoluminescentconstituents and a solar panel including the glass sheet. BACKGROUND

[0003] Solar panels are utilized to convert photons from the Sun to electrical energy. Solarpanels include one or more photovoltaic cells. Each photovoltaic cell includes two different semi-conductor materials (an n-type material and a p-type material) that are joined together to create a p-n junction. The n-type material includes, from a dopant, free electrons ready to move and thereby conduct electricity. The p-type material includes, from another dopant, free “holes” ready to accept the electrons and thereby conduct electricity. Upon application of thermal agitation, electrons from the n-type material cross the p-n junction and occupy a hole within the p-type material but additionally leaving behind a hole within the n-type material from where the electron came. An electric field is thus generated about the p-n junction (referred to as a depletion zone) with the n-type material having a positive charge (due to the loss of electrons) and the p-type material having a negative charge (due to the gain of electrons).

[0004] The Sun generates photons. The photovoltaic cell absorbs some of those photons. Ofthe absorbed photons, some photons have sufficient energy to cause electrons to move to the conduction band and thus leave a hole behind in the valence band. Minority carriers, for example electrons in the p-type material and holes in the n-type material, diffuse to the p-n junction. Because of the electric field at the depletion zone and high electron conductivity of the n-type material, the excited electrons move away from the depletion zone and to a primary surface of the n-type material. In a similar manner, the depletion zone electric field and high hole conductivity of the p-type material drive holes away from the depletion zone and to a primary surface of the of the p-type material. Assuming that conductors are coupled to both the primary surface of the n-type material and the p-type material, and the conductors are themselves electrically coupled, an electrical current is generated with the electrons moving from the n-type material, to the conductor at the primary surface of the n-type material, throughAttorney Docket No. SP24-152PCT the conductive material coupling the conductors, to the conductor at the primary surface of the p-type material, and then into the p-type material, occupying the holes that had migrated there. The flow of electrons to the primary surface of the n-type material of the photovoltaic cell creates a negative potential relative to ground.

[0005] However, there is a problem in that some of the photons from the Sun are too energeticfor the semi-conductor materials of the photovoltaic cells. Examples of such photons include those associated with the ultraviolet range of electromagnetic radiation (hereinafter referred to as “ultraviolet light”). Generally, the ability of the semiconductor material to absorb photons increases substantially in the ultraviolet range. This means ultraviolet light is absorbed within a shallow depth (less than 1 µm) near the surface of the photovoltaic cell. The excess energy carried by the electrons generated from the ultraviolet photons makes the electrons reactive with the passivation layer(s) formed or deposited on the semiconductor material surface. The reactions form defects in the structure of the passivation layer(s) and semiconductor material, for example, by breaking covalent chemical bonds and increasing the density of dangling bonds. These structural defects facilitate recombination of the photogenerated electron and holes, which reduces the open-circuit voltage of the photovoltaic cells and their ability to convert photons into electrical current as intended. The ultraviolet light-generated electron- hole pairs can introduce defects into the bulk semiconductor material through more complicated processes, such as by changing the charge state of impurities, increasing their ability to migrate into the bulk semiconductor and increase recombination there. The problem is exacerbated in Space-based solar panels because the Earth’s atmosphere is unable to filter the ultraviolet light before reaching the photovoltaic cells. Ultraviolet light additionally lowers the transmissivity of encapsulants of the photovoltaic cells over time, such as ethylene vinyl acetate (EVA), which further degrades overall performance of the photovoltaic cells.

[0006] In addition to the photovoltaic cells, the solar panels typically include a glass sheet asa cover over the photovoltaic cells. The glass sheet is substantially transparent to photons associated with wavelengths useful for the photovoltaic cells, such as those associated with the visible spectrum of electromagnetic radiation (hereinafter referred to as “visible light”). The glass sheet is often soda lime glass, which includes sodium ions (and / or other ions of alkali metals).

[0007] However, there is a further problem in that the negative potential at the primary surfaceof the n-type material causes sodium ions (or other alkali metal ions) to migrate out of the soda lime glass and into the n-type material of the photovoltaic cells. That is a problem, because the presence of those ions disrupts the arrangement of silicon and dopant atoms at the primaryAttorney Docket No. SP24-152PCT surface of the n-type material. The disrupted arrangement of those atoms traps the migration of electrons and holes throughout the n-type material. The trapping of such charge carriers decreases current generation (e.g., efficiency of the PV cell). The migrated ions degrade the photovoltaic cells in other ways as well. These degradations are collectively referred to as “potential induced degradation” or PID for short. Still further, a glass sheet made of soda lime glass cover is problematic because soda lime glass is relatively heavy. The weight of the soda lime glass derives, in part, because thick sheets are needed to provide enough mechanical support and rigidity of the panel. The weight of solar panels is thus a problem due to resource usage, shipping, weight load on building roofs, and associated costs. SUMMARY

[0008] There have been efforts to modify the glass sheet used as a cover for solar panels withone or more constituents that absorb ultraviolet light and release the absorbed energy as light of a different wavelength or wavelength range. However, those efforts have proven insufficient because not enough ultraviolet light is absorbed (and thus the ultraviolet light still degrades the components of the solar panel) and / or the released energy is not associated with wavelength(s) that are particularly useful for the photovoltaic cells to generate electrical current, and / or the low yield of released energy. For example, Eu and Ce ions in soda lime type glasses have low photoluminescence quantum yields (QY). Even with proper redox control Eu2+doped soda lime has a QY of less than 25% and Ce3+doped soda lime has a QY of less than 50% meaning that most of the UV photons are wasted and generate heat which further degrades the performance of the solar panel.

[0009] The present disclosure addresses these issues with a glass sheet with a composition thatincludes SiO2and either Eu2+or Ce3+ions or both Eu2+and Ce3+ions. The presence of divalent ions of Eu and / or trivalent ions of Ce permits the glass sheet to absorb a substantial percentage of ultraviolet light that would otherwise degrade the photovoltaic cells without hindering transmission of visible light that the photovoltaic cells utilize to generate electrical current. Further, the divalent ions of Eu and / or trivalent ions of Ce permit the glass sheet to exhibit photoluminescence that re-emits the absorbed ultraviolet light energy as visible light that the photovoltaic cells can again utilize to generate electrical current. In some aspects, the composition lacks sodium ions (and other alkali metal ions), the lack of which curtails potential induced degradation. Moreover, the glass sheet is fusion formable, which permits the glass sheet to be made with a relatively thin thickness, which reduces weight of the glass sheet andAttorney Docket No. SP24-152PCT thus the weight of a solar panel incorporating the glass sheet. Surprisingly, the glass sheet is able to re-emit more than 50% of the absorbed UV photons as visible light.

[0010] According to a first aspect of the present disclosure, a glass sheet comprises: a silicaglass composition comprising Eu2+ions, wherein, the glass sheet exhibits, at a thickness of 0.7 mm, (i) less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm, (ii) less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm, (iii) greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm, and (iv) a photoluminescence quantum yield of greater than 50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm.

[0011] According to a second aspect of the present disclosure, the glass sheet of the first aspectis presented, wherein the silica glass composition comprises (in mole percentage) from 60.0 to 99.5 SiO2.

[0012] According to a third aspect of the present disclosure, the glass sheet of any one of thefirst through second aspects is presented, wherein the silica glass composition comprises (in mole percentage): from 61 to 88 SiO2; from 0.05 to 30 Al2O3; from 0 to 25 B2O3; from 0 to 30 MgO; from 0 to 25 CaO; from 0 to 25 SrO; from 0 to 25 BaO; from 0 to 12 Na2O; and from 0 to 20 La2O3; wherein, R2O + (BeO + CaO + SrO + BaO) – Al2O3 – B2O3 is from -50 to 4 mol% of the glass composition, where R2O is the sum of all alkali oxides of the composition.

[0013] According to a fourth aspect of the present disclosure, the glass sheet of the third aspectis presented, wherein the silica glass composition comprises (in mole percentage): from 62.0 to 69.0 SiO2; from 12.0 to 22.0 Al2O3; and from 9.0 to 23.5 RO, wherein RO is the sum of MgO, CaO, SrO, BaO, and BeO.

[0014] According to a fifth aspect of the present disclosure, the glass sheet of the fourth aspectis presented, wherein the silica glass composition comprises (in mole percentage): from 10.0 to 20.0 MgO.

[0015] According to a sixth aspect of the present disclosure, the glass sheet of the fourth aspectis presented, wherein the silica glass composition comprises (in mole percentage): from 2.0 to 6.0 MgO; from 4.0 to 9.5 CaO; and from 0.25 to 4.5 SrO.

[0016] According to a seventh aspect of the present disclosure, the glass sheet of any one ofthe fourth through the sixth aspects is presented, wherein the silica glass composition comprises (in mole percentage): from 5.0 to 12.0 B2O3.

[0017] According to an eighth aspect of the present disclosure, the glass sheet of any one ofthe fourth through the seventh aspects is presented, wherein in the silica glass composition,Attorney Docket No. SP24-152PCT R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3– B2O3– (MgO / 4) is within a range of from -50 mol% to 12 mol%.

[0018] According to a ninth aspect of the present disclosure, the glass sheet of any one of thefourth through the eighth aspects is presented, wherein in the silica glass composition, (CaO + BaO) – Al2O3 – B2O3 is less than -11 mol%.

[0019] According to a tenth aspect of the present disclosure, the glass sheet of any one of thefirst through the ninth aspects is presented, wherein the silica glass composition comprises (in mole percentage) from 0.0025 to 1.0 of a sum of Eu2O3 and EuO.

[0020] According to an eleventh aspect of the present disclosure, the glass sheet of the tenthaspect is presented, wherein the silica glass composition comprises (in mole percentage) from 0.005 to 0.17 of the sum of Eu2O3and EuO.

[0021] According to a twelfth aspect of the present disclosure, the glass sheet of any one of thefirst through eleventh aspects is presented, wherein the silica glass composition is substantially free of cerium, any cerium oxide, and ions of cerium.

[0022] According to a thirteenth aspect of the present disclosure, the glass sheet of any one ofthe first through twelfth aspects is presented, wherein the silica glass composition is a product of mixing, melting, and forming the glass sheet from a batch composition that includes (in mole percentage): from greater than 0 to 0.60 of a reducing agent.

[0023] According to a fourteenth aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising Ce3+ions, wherein, the glass sheet exhibits, at a thickness of 0.7 mm, (i) less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm, (ii) less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm, (iii) greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm, and (iv) a photoluminescence quantum yield of greater than 50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm.

[0024] According to a fifteenth aspect of the present disclosure, the glass sheet of thefourteenth aspect is presented, wherein the silica glass composition comprises (in mole percentage) from 60.0 to 99.5 SiO2.

[0025] According to a sixteenth aspect of the present disclosure, the glass sheet of thefourteenth aspect is presented, wherein the silica glass composition comprises (in mol%): from 60 to 75 SiO2; from 0.3 to 20 Al2O3; from 0 to 25 B2O3; from 0 to 30 MgO; from 0 to 20 CaO; from 0 to 20 SrO; and from 0 to 20 BaO; wherein, R2O + (BeO + MgO + CaO + SrO + BaO)Attorney Docket No. SP24-152PCT – Al2O3– B2O3is from -50 to 4 mol% of the glass composition, where R2O is the sum of all alkali oxides of the glass composition.

[0026] According to a seventeenth aspect of the present disclosure, the glass sheet of thesixteenth aspect is presented, wherein the silica glass composition comprises (in mol%): from 62.0 to 69.0 SiO2; from 12.0 to 22.5 Al2O3; and from 11.5 to 22.5 RO, wherein RO is the sum of MgO, CaO, SrO, BaO, and BeO.

[0027] According to an eighteenth aspect of the present disclosure, the glass sheet of any oneof the sixteenth through seventeenth aspects is presented, wherein the silica glass composition comprises (in mol%): from 10.0 to 23.0 MgO.

[0028] According to a nineteenth aspect of the present disclosure, the glass sheet of any one ofthe sixteenth through eighteenth aspects is presented, wherein the silica glass composition comprises (in mole percentage): from 5.0 to 12.0 B2O3.

[0029] According to a twentieth aspect of the present disclosure, the glass sheet of the sixteenthaspect is presented, wherein the silica glass composition comprises (in mole percentage): from 65.0 to 75.0 SiO2; from 3.0 to 4.0 Al2O3; from 15.0 to 25.0 B2O3; >0 Li2O; >0 Na2O; and>0 CaO.

[0030] According to a twenty-first aspect of the present disclosure, the glass sheet of any oneof the sixteenth through twentieth aspects is presented, wherein R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 is from -25 to 4 mol% of the composition, where R2O is the sum of all alkali oxides of the glass composition.

[0031] According to a twenty-second aspect of the present disclosure, the glass sheet of anyone of the sixteenth through twenty-first aspects is presented, wherein(BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -25 to 15 mol% of the composition.

[0032] According to a twenty-third aspect of the present disclosure, the glass sheet of thefourteenth aspect is presented, wherein the silica glass composition further comprises (in mol%): from 60.0 to 69.9 SiO2; from 0.1 to 22.0 Al2O3; from 0 to 17.0 B2O3; from 0 to 1.75 of a sum of Li2O and Na2O; from 0 to 0.05 Fe2O3; from 0 to 0.25 TiO2; from 0 to 1.0 PbO; and from 0 to 0.1 As2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 0.85 mol% of the composition.

[0033] According to a twenty-fourth aspect of the present disclosure, the glass sheet of thefourteenth aspect is presented, wherein the silica glass composition further comprises (in mol%): from 60.0 to 69.9 SiO2; from 0.1 to 22.0 Al2O3; from 0 to 25.0 B2O3; from 0 to 1.75 of a sum of Li2O and Na2O; from 0 to 0.05 Fe2O3; from 0 to 1 PbO; from 0 to 0.4 of a sum ofAttorney Docket No. SP24-152PCT Sb2O3, Yb2O3, and Y2O3; and from 0 to 0.1 As2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 0.85 mol% of the composition.

[0034] According to a twenty-fifth aspect of the present disclosure, the glass sheet of thefourteenth aspect is presented, wherein the silica glass composition further comprises (in mol%): from 60.0 to 75.0 SiO2; from 0.1 to 25.0 Al2O3; from 0 to 9.25 B2O3; from 0 to 1 BaO; from 0 to 1.75 of the sum of Li2O and Na2O; from 0 to 0.25 TiO2; from 0 to 1 PbO; and from 0 to 0.5 of a sum of La2O3, Y2O3, Pr2O3, Nd2O3, Tm2O3, Er2O3, Ho2O3, Lu2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 3.0 mol% of the composition.

[0035] According to a twenty-sixth aspect of the present disclosure, the glass sheet of thetwenty-fifth aspect is presented, wherein the silica glass composition comprises (in mol%): from 0 to 3 B2O3; and from 0 to 0.1 of the sum of La2O3, Y2O3, Pr2O3, Nd2O3, Tm2O3, Er2O3, Ho2O3, Lu2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 2.2 mol% of the composition.

[0036] According to a twenty-seventh aspect of the present disclosure, the glass sheet of anyone of the fourteenth through twenty-sixth aspects is presented, wherein the silica glass composition further comprises (in mol%): from 0.025 to 0.5 of a sum of Ce2O3 and CeO2.

[0037] According to a twenty-eighth aspect of the present disclosure, the glass sheet of thetwenty-seventh aspect is presented, wherein the silica glass composition comprises (in mol%): from 0.04 to 0.35 of the sum of Ce2O3 and CeO2.

[0038] According to a twenty-ninth aspect of the present disclosure, the glass sheet of any oneof the fourteenth through twenty-eighth aspects is presented, wherein the silica glass composition is substantially free of europium, any europium oxide, and ions of europium.

[0039] According to a thirtieth aspect of the present disclosure, the glass sheet of any one ofthe fourteenth through twenty-ninth aspects is presented, wherein the silica glass composition is a product of mixing, melting, and forming the glass sheet from a batch composition that includes (in mole percentage): from greater than 0 to 0.60 of a reducing agent.

[0040] According to a thirty-first aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising Eu2+ion and Ce3+ions, wherein, the glass sheet exhibits, at a thickness of 0.7 mm, (i) less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm, (ii) less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm, (iii) greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm, and (iv) a photoluminescence quantum yield of greater than 50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm.Attorney Docket No. SP24-152PCT

[0041] According to a thirty-second aspect of the present disclosure, the glass sheet of thethirty-first aspect is presented, wherein the silica glass composition comprises (in mol%): from 55 to 88 SiO2; from 0 to 30 Al2O3; from 0 to 25 B2O3; from 0 to 30 MgO; from 0 to 20 CaO; from 0 to 20 SrO; and from 0 to 20 BaO; wherein, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 is from -50 to 4 mol% of the glass composition, where R2O is the sum of all alkali oxides of the glass composition.

[0042] According to a thirty-third aspect of the present disclosure, the glass sheet of the thirty-second aspect is presented, wherein R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 is from -25 to 4 mol% of the glass composition.

[0043] According to a thirty-fourth aspect of the present disclosure, the glass sheet of any oneof the thirty-second through the thirty-third aspects is presented, wherein the silica glass composition comprises (in mol%): from 62 to 70 SiO2; from 10 to 20 Al2O3; from 4.0 to 10.0 B2O3; from 2.0 to 6.0 MgO; from 3.0 to 9.2 CaO; and from 0.30 to 4.5 SrO.

[0044] According to a thirty-fifth aspect of the present disclosure, the glass sheet of the thirty-first aspect is presented, wherein the silica glass composition comprises: greater than or equal to 61.0 SiO2; from 0.01 to 1.0 of the sum of Eu2O3 and EuO; and greater than 0.01 of the sum of Ce2O3and CeO2; and R2O + (BeO + CaO + SrO + BaO + ZnO) – Al2O3– B2O3is from -50 to 10 mol% of the silica glass composition, where R2O is the sum of all alkali oxides of the glass composition.

[0045] According to a thirty-sixth aspect of the present disclosure, the glass sheet of the thirty-first aspect is presented, wherein the silica glass composition comprises: from 61.0 to 99.95 SiO2; from 0 to 12.5 Na2O; from 0.005 to 0.17 of the sum of Eu2O3 and EuO; from 0 to 0.05 Fe2O3; from 0 to 0.3 TiO2; from 0 to 4.0 ZrO2; and greater than 0 of the sum of Ce2O3 and CeO2; and Al2O3 / (Eu2O3+ Ce2O3+ CeO2 / 2) is greater than or equal to 3.5 mol% of the silica glass composition.

[0046] According to a thirty-seventh aspect of the present disclosure, the glass sheet of anyone of the thirty-first through the thirty-sixth aspects is presented, wherein the silica glass composition further comprises: from 0.0025 to 0.5 of the sum of Eu2O3 and EuO; and from 0.020 to 0.5 of the sum of Ce2O3 and CeO2.

[0047] According to a thirty-eighth aspect of the present disclosure, the glass sheet of any oneof the thirty-first through the thirty-seventh aspects is presented, wherein the silica glass composition is substantially free of terbium, any terbium oxide, and ions of terbium.

[0048] According to a thirty-ninth aspect of the present disclosure, the glass sheet of any oneof the thirty-first through the thirty-eighth aspects is presented, wherein the silica glassAttorney Docket No. SP24-152PCT composition is a product of mixing, melting, and forming the glass sheet from a batch composition that includes (in mole percentage): from greater than 0 to 0.60 of a reducing agent.

[0049] According to a fortieth aspect of the present disclosure, a glass sheet comprises: a silicaglass composition comprising (in mol%): from 61.0 to 88.0 SiO2; greater than or equal to 0.05 Al2O3; from 0 to 12.5 Na2O; from 0.005 to 0.5 of a sum of Eu2O3 and EuO; from 0 to 0.3 TiO2; and from 0 to 4.0 ZrO2; wherein, in the silica glass composition, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3– B2O3– (MgO / 4) is within a range of from -50 mol% to 4.5 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.

[0050] According to a forty-first aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising (in mol%): from 60.0 to 69.9 SiO2; from 0.1 to 22.0 Al2O3; from 0 to 17.0 B2O3; from 0.04 to 0.35 of a sum of Ce2O3and CeO2; from 0 to 0.05 Fe2O3; from 0 to 0.25 TiO2; from 0 to 1.0 PbO; and from 0 to 0.1 As2O3; wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3 is within a range of from -40 mol% to 0.85 mol%, and wherein, in the silica glass composition, the sum of Li2O + Na2O is from 0 to 1.75 mol%.

[0051] According to a forty-second aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising (in mol%): greater than or equal to 61.0 SiO2; from 0 to 0.65 F; from 0.01 to 1.0 Eu2O3; and greater than or equal to 0.01 of a sum of CeO2 and Ce2O3; wherein, in the silica glass composition, R2O + (BeO + CaO + SrO + BaO + ZnO) – Al2O3 – B2O3is within a range of from -50 mol% to 10 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.

[0052] According to a forty-third aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising (in mol%): from 61.0 to 95.0 SiO2; from 0 to 12.5 Na2O; from 0 to 0.65 F; from 0.005 to 0.17 of a sum of Eu2O3and EuO; from 0 to 0.3 Ti2O; and from 0 to 4.0 ZrO2; wherein, in the silica glass composition, R2O + (BeO + MgO + CaO + SrO + BaO ) – Al2O3 – B2O3 – (MgO / 4) is within a range of from -50 mol% to 12 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.

[0053] According to a forty-fourth aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising (in mol%): greater than or equal to 61.0 SiO2; from 0.01 to 1.0 Eu2O3; greater than or equal 0.01 of a sum of Ce2O3and CeO2; and from 0 to 0.05 Tb2O3; wherein, in the silica glass composition, R2O + (BeO + CaO + SrO + BaO + ZnO) – Al2O3– B2O3 is within a range of from -50 mol% to 10 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.Attorney Docket No. SP24-152PCT

[0054] According to a forty-fifth aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising (in mol%): from 60.0 to 69.9 SiO2; from 0.1 to 22.0 Al2O3; from 0 to 25.0 B2O3; from 0.04 to 0.35 of a sum of Ce2O3 and CeO2; from 0 to 0.05 Fe2O3; from 0 to 0.25 TiO2; from 0 to 1.0 PbO; and from 0 to 0.1 As2O3; wherein, in the silica glass composition, Li2O + Na2O is within a range of from 0 mol% to 1.75 mol%, wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3 is within a range of from -40 mol% to 0.85 mol%, and wherein, in the silica glass composition, Sb2O3+Yb2O3+ Y2O3is within a range of from 0 to 0.4 mol%.

[0055] According to a forty-sixth aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising (in mol%): from 60.0 to 75.0 SiO2; from 0.10 to 25.0 Al2O3; from 0 to 3.0 B2O3; from 0 to 1.0 BaO; from 0.04 to 0.35 of a sum of Ce2O3and CeO2; from 0 to 0.25 TiO2; and from 0 to 1 PbO; wherein, in the silica glass composition, Li2O + Na2O is within a range of from 0 to 1.75 mol%, wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3is within a range of from -40 mol% to 2.2 mol%, and wherein, in the silica glass composition, La2O3 + Y2O3 + Pr2O3 + Nd2O3 + Tm2O3 + Er2O3 + Ho2O3 + Lu2O3 is within a range of from 0 to 0.5 mol%.

[0056] According to a forty-seventh aspect of the present disclosure, a glass sheet comprises:a silica glass composition comprising (in mol%): from 60.0 to 75.0 SiO2; from 0.1 to 25.0 Al2O3; from 0 to 9.35 B2O3; and from 0 to 1.0 BaO; from 0.04 to 0.35 of a sum of Ce2O3 and CeO2; from 0 to 1.0 PbO; and from 0 to 0.25 TiO2; wherein, in the silica glass composition, Li2O + Na2O is within a range of from 0 to 1.75 mol%, wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3 is within a range of from -40 mol% to 3.0 mol%, and wherein, in the silica glass composition, La2O3 + Y2O3 + Pr2O3 + Nd2O3 + Gd2O3 + Tm2O3 + Er2O3+ Ho2O3+ Lu2O3is within a range of from 0 to 0.1 mol%.

[0057] According to a forty-eighth aspect of the present disclosure, a glass sheet comprises: asilica glass composition comprising (in mol%): from 61.0 to 99.95 SiO2; from 0 to 12.5 NaO2; from 0 to 0.65 F; from 0.005 to 0.17 of a sum of Eu2O3and EuO; from 0 to 0.05 Fe2O3; from 0 to 0.3 TiO2; and from 0 to 4.0 ZrO2; wherein, in the silica glass composition, Al2O3 / (Eu2O3 + Ce2O3 + (CeO2 / 2) is greater than or equal to 3.5 mol%.

[0058] According to a forty-ninth aspect of the present disclosure, a solar panel comprises: oneor more photovoltaic cells; and the glass sheet of any one of the first through the forty-eighth aspects positioned relative to the one or more photovoltaic cells such that electromagnetic radiation transmits through the glass sheet and impinges upon the one or more photovoltaic cells.Attorney Docket No. SP24-152PCT

[0059] According to a fiftieth aspect of the present disclosure, the solar panel of the forty-ninthaspect is presented, wherein (i) the glass sheet comprises a first primary surface, a second primary surface, and a thickness between the first primary surface and the second primary surface, and (ii) the thickness of the glass sheet is less than 1.0 mm.

[0060] Additional features and advantages will be set forth in the detailed description whichfollows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.

[0061] It is to be understood that both the foregoing general description and the followingdetailed description are merely exemplary, and are intended to provide an overview or framework to understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiments, and together with the description serve to explain principles and operation of the various embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In the Drawings:

[0063] FIG. 1 is a perspective view of a glass sheet of the present disclosure, illustrating a firstprimary surface, a second primary surface, and a thickness therebetween;

[0064] FIG. 2 is perspective view of a solar panel incorporating the glass sheet, illustrating theglass sheet positioned to face the Sun to accept photons that are transmitted through the glass sheet to one or more photovoltaic cells that the glass sheet covers;

[0065] FIG. 3 is a plan view of the solar panel;

[0066] FIG. 4 is an elevation view of a cross-section of the solar panel taken through line IV-IV of FIG.3, illustrating the glass sheet and the one or more photovoltaic cells combined as a package held by a frame;

[0067] FIG. 5 is an elevation view of area V of FIG. 4, illustrating the package including theglass sheet, a first polymer layer, the one or more photovoltaic cells, a second polymer layer, and a backsheet;

[0068] FIG. 6, pertaining to various examples, is a graph illustrating that the glass sheet canexhibit a photoluminescence quantum yield of greater than 50% when, in the composition, R2O + (BeO + CaO + SrO + BaO) − Al2O3− B2O3is less than or equal to 4 mol%;

[0069] FIG. 7, pertaining to various examples, is a graph plotting photoluminescence quantumyield and peak emission wavelength as a function of CaO + BaO − Al2O3 − B2O3 (in mole percentage) of the composition, illustrating (i) that photoluminescence quantum yieldAttorney Docket No. SP24-152PCT decreases as CaO + BaO − Al2O3− B2O3(in mole percentage) of the composition increases and (ii) that photoluminescence emission wavelength increases as CaO + BaO − Al2O3 − B2O3 (in mole percentage) of the composition increases;

[0070] FIG. 8, pertaining to various examples, is a graph plotting transmission as a function ofwavelength of electromagnetic radiation being transmitted for a comparative example soda lime glass sheet and selected glass sheets of the present disclosure, illustrating that the inclusion of Eu2O3, and Eu2O3and Ce2O3, in the composition decreases transmission of ultraviolet light through the glass sheet;

[0071] FIG. 9, pertaining to various examples, is a graph plotting photons emitted afterexcitation due to photoluminescence as a function of wavelength of the exciting photon or wavelength of the photon emitted for selected glass sheets of the present disclosure, illustrating that the glass sheets emit photons associated with the visible spectrum after excitation with photons associated with the ultraviolet range;

[0072] FIG.10A, pertaining to a comparative example with soda lime glass, is a graph plottingcurrent as a function of voltage for a bare photovoltaic cell, the photovoltaic cell soldered with a bus bar, and a solar module with the soda lime glass covering the photovoltaic cell; and

[0073] FIG. 10B, pertaining to an example glass sheet of the present disclosure, is a graphplotting current as a function of voltage for a bare photovoltaic cell, the photovoltaic cell soldered with a bus bar, and a solar module with the glass sheet covering the photovoltaic cell, illustrating that the solar module with the glass sheet of the present disclosure increases the short-circuit current relative to the soldered photovoltaic cell more than the solar module with the soda lime glass. DETAILEDDESCRIPTION

[0074] Reference will now be made in detail to the present preferred embodiments, examplesof which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.

[0075] Referring to FIG. 1, a glass sheet 10 of the present disclosure is herein disclosed. Theglass sheet 10 includes a silica glass composition. The glass sheet 10 has a first primary surface 12, a second primary surface 14, and a thickness 16. The first primary surface 12 and the second primary surface 14 can face in generally opposite directions and can each be substantially planar. The thickness 16 of the glass sheet 10 is the shortest straight-line distance between the first primary surface 12 and the second primary surface 14. In embodiments, the thickness 16 is less than 2.0 mm. For example, the thickness 16 of the glass sheet 10 can be 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3Attorney Docket No. SP24-152PCT mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm or within any range bound by any two of those values (e.g., from 0.4 mm to 0.8 mm, from 0.6 mm to 0.9 mm, and so on). The thickness 16 of the glass sheet 10 can be greater than 2.0 mm. In embodiments, the glass sheet 10 is a sheet of a laminate that includes one or more additional sheets. The one or more additional sheets can have a different composition than the glass composition of the glass sheet 10 of the present disclosure.

[0076] The silica glass composition of the glass sheet 10 is made includes Eu2+ ions, Ce3+ ions,or both Eu2+ion and Ce3+ions. In all instances, the glass sheet of the present disclosure exhibits, at a thickness 16 of 0.7 mm, less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm. For example, the glass sheet 10 can exhibit less than 40% transmission therethrough (when the thickness 16 of the glass sheet 10 is 0.7 mm) of electromagnetic radiation through an entirety of a wavelength range of from 200 nm to 325 nm. In addition, the glass sheet 10 exhibits less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm. However, the glass sheet 10 exhibits greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm. In other embodiments the glass sheet 10 exhibits greater than 80% transmission throughout an entirety of a wavelength range of from 400 nm to 1150 nm. In other embodiments the glass sheet 10 exhibits greater than 80% transmission throughout an entirety of a wavelength range of from 420 nm to 1250 nm. In other embodiments the glass sheet 10 exhibits greater than 80% transmission throughout an entirety of a wavelength range of from 390 nm to 1100 nm. Transmission, for purposes of this disclosure, is determined using a PerkinElmer Lambda 900 spectrophotometer with a scan range of 200 nm to 3200 nm, and a scan step of 1 nm. Transmission is reported as direct transmission of polished samples without antireflective coatings.

[0077] The glass sheet 10 further exhibits a photoluminescence quantum yield of greater than50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm. The photoluminescence quantum yield that the glass sheet 10 exhibits, when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm, can be greater than 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99.9%, or within any range bound by any two of those values (e.g., from 55% to 85%, from 65% to 95%, and so on). The wavelength of the electromagnetic radiation exciting the glass sheet 10 to produce such a photoluminescence quantum yield can be 280 nm, 290 nm, 300 nm, 310 nm, 320 nm, 330 nm, 340 nm, 350 nm, 360 nm, 370 nm, or within any range bound by any two of those values (e.g., from 290 nm to 350 nm, from 310 nm to 330 nm, and so on).Attorney Docket No. SP24-152PCT

[0078] For purposes of this disclosure, photoluminescence is measured using a double gratingEdinburgh Scientific FLS1000 fluorimeter, and QY measurements are made using a 120 mm integrating sphere and measuring the excitation and emission of the sample and the empty sphere. The increase in emission peak area with the sample divided by the decrease in excitation peak area with the sample gives the ratio of photons emitted to photons absorbed which is the photoluminescence quantum yield QY.

[0079] A spectrofluorometer measures the photoluminescence of a material by illuminating asample at a known wavelength and measuring the emitted light with a photomultiplier tube. The sample is placed in a chamber between two independently controlled monochromators. A broadband light source is used with emission from near ultraviolet, through the visible spectrum and into the near infrared. A 500W xenon arc lamp was used. For an emission scan, a first monochromator, disposed directly after a lamp, is tuned to an absorption band of the test sample. A second monochromator, disposed directly after the sample chamber, is scanned over a given range and the emitted light is measured by the photomultiplier tube, forming the photoluminescent emission (PL) spectrum. For the excitation spectrum, the second monochromator is set to a known emission band, and the first monochromator is scanned over a given range, measuring the photoluminescent excitation (PLE) spectrum. Measurements of the PLE were normalized to the spectrum of the xenon lamp, which varies over its emission spectrum, for an accurate PLE spectrum.

[0080] The efficiency in which a photoluminescent material converts light from onewavelength to another can be described as photoluminescent quantum yield (QY). While it is possible to determine the QY of a material by comparing the absorption, PL and PLE spectra of a test composition to a reference composition, the QY may be measured more directly using a spectrometer coupled integration sphere, where the absorption and PL spectra of a composition are referenced against a blank reference sample. The quantum yield, as a percentage, is typically calculated from the standard formula:

[0081] where φ is the number of photons measured by the spectrometer in the range 250-380nm with the superscript inc and 300-850 nm when the superscript em is used. The subscriptsamp indicates the measurement of the luminescent sample, and the subscript ref indicates ameasurement of an appropriate blank reference sample. For a typical measurement, the reference is a 10 mm spectralon disk.Attorney Docket No. SP24-152PCT

[0082] Silicon dioxide, SiO2, is the primary glass former in the silica glass composition. Themole percentage of the SiO2 in these embodiments of the silica glass composition is within a range of from 55.0 mol% to 99.5 mol%. The mole percentage of SiO2 in these embodiments of the composition can be 55.0 mol%, 56.0 mol%, 57.0 mol%, 58.0 mol%, 59.0 mol%, 60.0 mol%, 61.0 mol%, 62.0 mol%, 63.0 mol%, 64.0 mol%, 65.0 mol%, 66.0 mol%, 67.0 mol%, 68.0 mol%, 69.0 mol%, 69.9 mol%, 70.0 mol%, 71.0 mol%, 72.0 mol%, 73.0 mol%, 74.0 mol%, 75.0 mol%, 76.0 mol%, 77.0 mol%, 78.0 mol%, 79.0 mol%, 80.0 mol%, 81.0 mol%, 82.0 mol%, 83.0 mol%, 84.0 mol%, 85.0 mol%, 86.0 mol%, 87.0 mol%, 88.0 mol%, 89.0 mol%, 90.0 mol%, 91.0 mol%, 92.0 mol%, 93.0 mol%, 94.0 mol%, 95.0 mol%, 96.0 mol%, 97.0 mol%, 98.0 mol%, 99.0 mol%, 99.5 mol%, or within any range bound by any two of those values (e.g., from 60.0 mol% to 75.0 mol%, from 60.0 mol% to 99.5 mol% SiO2, from 60.0 mol% to 88.0 mol%, from 62.0 mol% to 69.0 mol%, from 60.0 mol% to 69.9 mol%, from 68.0 mol% to 84.0 mol%, from 71.0 mol% to 76.0 mol%, from 65.0 mol% to 75.0 mol%, from 55.0 mol% to 88.0 mol%, from 62.0 mol% to 70.0 mol%, from mol% 61.0 to 99.5 mol%, and so on).

[0083] In embodiments, the silica glass composition further includes aluminum oxide, Al2O3,as another glass former of the composition. The mole percentage of Al2O3in these embodiments of the silica glass composition is within a range of from 0 mol% to 30.0 mol%. The mole percentage of Al2O3 in these embodiments of the silica composition can be 0 mol%, greater that 0 mol%, 0.05 mol%, 0.10 mol%, 0.20 mol%, 0.30 mol%, 0.40 mol%, 0.50 mol%, 1.0 mol%, 2.0 mol%, 3.0 mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 10.0 mol%, 11.0 mol%, 12.0 mol%, 13.0 mol%, 14.0 mol%, 15.0 mol%, 16.0 mol%, 17.0 mol%, 18.0 mol%, 19.0 mol%, 20.0 mol%, 21.0 mol%, 22.0 mol%, 22.5 mol%, 23.0 mol%, 24.0 mol%, 25.0 mol%, 26.0 mol%, 27.0 mol%, 28.0 mol%, 29.0 mol%, 30.0 mol%, or within any range bound by any two of those values (e.g., from 1.0 mol% to 23.0 mol%, from 12.0 mol% to 15.0 mol%, from 12.0 mol% to 22.0 mol%, from 0.30 mol% to 20.0 mol%, from 12.0 mol% to 22.5 mol%, from 3.0 mol% to 4.0 mol%, from 0.10 mol% to 22.0 mol%, from 0.10 mol% to 25.0 mol%, from 0.05 mol% to 30.0 mol%, from 10.0 mol% to 20.0 mol%, and so on).

[0084] In embodiments, the silica glass composition further includes boron trioxide, B2O3, anadditional glass former of the silica glass composition. The mole percentage of B2O3in these embodiments of the silica glass composition is within a range of from 0 mol% to 25.0 mol%. The mole percentage of B2O3 in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.50 mol%, 1.0 mol%, 2.0 mol%, 3.0Attorney Docket No. SP24-152PCT mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 9.25 mol%, 10.0 mol%, 11.0 mol%, 12.0 mol%, 13.0 mol%, 14.0 mol%, 15.0 mol%, 16.0 mol%, 17.0 mol%, 18.0 mol%, 19.0 mol%, 20.0 mol%, 21.0 mol%, 22.0 mol%, 23.0 mol%, 24.0 mol%, 25.0 mol%, or within any range bound by any two of those values (e.g., from 1.0 mol% to 23.0 mol%, from 12.0 mol% to 15.0 mol%, from 5.0 mol% to 12.0 mol%, from 15.0 mol% to 25.0 mol%, from 0 mol% to 17.0 mol%, from 0 mol% to 9.25 mol%, from 0 to 3.0 mol%, from 4.0 mol% to 10.0 mol%, and so on). The silica glass composition can be substantially free or free of B2O3. “Substantially free” in this disclosure means that the composition (and the substrate) does not intentionally include any of the mentioned constituent but the constituent may be present in a small amount due to manufacturing imperfections (e.g., a measurable amount less than 0.05 mol%).

[0085] In embodiments, the silica glass composition further includes magnesium oxide, MgO,as a modifier and / or intermediate. The mole percentage of MgO in these embodiments of the composition is within a range of from 0 mol% to 30.0 mol%. The mole percentage of MgO in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.50 mol%, 1.0 mol%, 2.0 mol%, 3.0 mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 10.0 mol%, 11.0 mol%, 12.0 mol%, 13.0 mol%, 14.0 mol%, 15.0 mol%, 16.0 mol%, 17.0 mol%, 18.0 mol%, 19.0 mol%, 20.0 mol%, 21.0 mol%, 22.0 mol%, 23.0 mol%, 24.0 mol%, 25.0 mol%, 26.0 mol%, 27.0 mol%, 28.0 mol%, 29.0 mol%, 30.0 mol%, or within any range bound by any two of those values (e.g., from 1.0 mol% to 23.0 mol%, from 12.0 mol% to 15.0 mol%, from 10.0 mol% to 20.0 mol%, from 2.0 mol% to 6.0 mol%, from 10.0 mol% to 23.0 mol%, and so on). The silica glass composition can be substantially free or free of MgO. MgO can act as both a modifier and intermediate due to the small ionic radius and high field strength of Mg2+, so MgO is often treated as both modifier and intermediate and commonly only a fraction of the MgO is considered a modifier such as ½, ⅓, or ¼ depending on the base glass it is in.

[0086] In embodiments, the silica glass composition further includes calcium oxide, CaO, as amodifier. The mole percentage of CaO in these embodiments of the silica glass composition is within a range of from 0 mol% to 25.0 mol%. The mole percentage of CaO in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.50 mol%, 1.0 mol%, 2.0 mol%, 3.0 mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 9.2 mol%, 9.5 mol%, 10.0 mol%, 11.0 mol%, 12.0 mol%, 13.0 mol%, 14.0 mol%, 15.0 mol%, 16.0 mol%, 17.0 mol%, 18.0 mol%, 19.0 mol%, 20.0 mol%, 21.0 mol%, 22.0 mol%, 23.0 mol%, 24.0 mol%, 25.0 mol%, or within any range bound by anyAttorney Docket No. SP24-152PCT two of those values (e.g., from 1 mol% to 23.0 mol%, from 12.0 mol% to 15.0 mol%, from 4.0 mol% to 9.5 mol%, from 0 mol% to 20.0 mol%, from 3.0 mol% to 9.2 mol%, and so on). The silica glass composition can be substantially free or free of CaO.

[0087] In embodiments, the silica glass composition further includes strontium oxide, SrO, asa modifier. The mole percentage of SrO in these embodiments of the silica glass composition is within a range of from 0 mol% to 25.0 mol%. The mole percentage of SrO in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.25 mol%, 0.30 mol%, 0.50 mol%, 1.0 mol%, 2.0 mol%, 3.0 mol%, 4.0 mol%, 4.5 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 10.0 mol%, 11.0 mol%, 12.0 mol%, 13.0 mol%, 14.0 mol%, 15.0 mol%, 16.0 mol%, 17.0 mol%, 18.0 mol%, 19.0 mol%, 20.0 mol%, 21.0 mol%, 22.0 mol%, 23.0 mol%, 24.0 mol%, 25.0 mol%, or within any range bound by any two of those values (e.g., from 1.0 mol% to 23.0 mol%, from 12.0 mol% to 15.0 mol%, from 0.25 mol% to 4.5 mol%, from 0 mol% to 20.0 mol%, from 0.30 mol% to 4.5 mol%, and so on). The silica glass composition can be substantially free or free of SrO.

[0088] In embodiments, the silica glass composition further includes barium oxide, BaO, as amodifier. The mole percentage of BaO in these embodiments of the silica glass composition is within a range of from 0 mol% to 25.0 mol%. The mole percentage of BaO in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.50 mol%, 1.0 mol%, 2.0 mol%, 3.0 mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 10.0 mol%, 11.0 mol%, 12.0 mol%, 13.0 mol%, 14.0 mol%, 15.0 mol%, 16.0 mol%, 17.0 mol%, 18.0 mol%, 19.0 mol%, 20.0 mol%, 21.0 mol%, 22.0 mol%, 23.0 mol%, 24.0 mol%, 25.0 mol%, or within any range bound by any two of those values (e.g., from 1.0 mol% to 23.0 mol%, from 12.0 mol% to 15.0 mol%, from 0 mol% to 1.0 mol%, and so on). The silica glass composition can be substantially free or free of BaO. The explicit mention of the alkaline earth oxides MgO, CaO, SrO, and BaO does not preclude the inclusion of BeO and / or RaO in the composition. Although incorporation of BaO is useful to decrease liquidus temperature and increase liquidus viscosity, other considerations might lead to limiting the amount of BaO included or omitting BaO from the silica glass composition entirely.

[0089] For purposes of this disclosure, RO means the sum of MgO, CaO, SrO, BaO, and BeO.In embodiments, the mole percentage of RO in the silica glass composition is within a range of from 0 mol% to 23.5 mol%. For example, the mole percentage of RO can be 0 mol%, 1.0 mol%, 2.0 mol%, 3.0 mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 10.0 mol%, 11.0 mol%, 11.5 mol%, 12.0 mol%, 13.0 mol%, 14.0 mol%, 15.0 mol%, 16.0 mol%, 17.0 mol%, 18.0 mol%, 19.0 mol%, 20.0 mol%, 21.0 mol%, 22.0 mol%, 22.5 mol%,Attorney Docket No. SP24-152PCT 23.0 mol%, 23.5 mol%, or within any range bound by any two of those values (e.g., from 9.0 mol% to 23.5 mol%, from 11.5 mol% to 22.5 mol%, and so on).

[0090] In embodiments, in the silica glass composition, (CaO + BaO) – Al2O3 – B2O3 is lessthan -11 mol%. For example, (CaO + BaO) - Al2O3- B2O3can be -30 mol%, -29 mol%, -28 mol%, -27 mol%, -26 mol%, -25 mol%, -24 mol%, -23 mol%, -22 mol%, -21 mol%, -20 mol%, -19 mol%, -18 mol%, -17 mol%, -16 mol%, -15 mol%, -14 mol%, -13 mol%, -12 mol%, less than -11 mol%, or within any range bound by any two of those values (e.g., from -29 mol% to less than -11 mol%, from -25 mol% to -15 mol%, and so on).

[0091] In embodiments, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) –Al2O3is from -40 to 15 mol% of the composition. For example, (BeO + MgO + CaO + SrO + BaO) – Al2O3can be -40 mol%, -39 mol%, -38 mol%, -37 mol%, -36 mol%, -35 mol%, -34 mol%, -33 mol%, -32 mol%, -31 mol%, -30 mol%, -29 mol%, -28 mol%, -27 mol%, -26 mol%, -25 mol%, -24 mol%, -23 mol%, -22 mol%, -21 mol%, -20 mol%, -19 mol%, -18 mol%, -17 mol%, -16 mol%, -15 mol%, -14 mol%, -13 mol%, -12 mol%, -11 mol%, -10 mol%, -9 mol%, -8 mol%, -7 mol%, -6 mol%, -5 mol%, -4 mol%, -3 mol%, -2 mol%, -1 mol%, 0 mol%, 0.85 mol%, 1 mol%, 2 mol%, 2.2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, or within any range bound by any two of those values (e.g., from -10 mol% to 10 mol%, from -40 mol% to 2.2 mol%, from -13 mol% to 0 mol%, -40 mol% to 3.0 mol%, from -40 mol% to 0.85 mol%, and so on).

[0092] In embodiments, in the silica glass composition, R2O + (BeO + CaO + SrO + BaO +ZnO) – Al2O3– B2O3is within a range of from -50 mol% to 10 mol%. For example, R2O + (BeO + CaO + SrO + BaO + ZnO) – Al2O3 – B2O3 can be -50 mol%, -45 mol%, -40 mol%, - 35 mol%, -30 mol%, -25 mol%, -20 mol%, -15 mol%, -10 mol%, -5 mol%, 0, 5 mol%, 10 mol%, or within any range bound by any two of those values (e.g., from -40 mol% to -15 mol%, from -15 mol% to 0, and so on).

[0093] In embodiments, the silica glass composition further includes sodium oxide, Na2O, asa modifier. The mole percentage of Na2O in these embodiments of the silica glass composition is within a range of from 0 mol% to 12.5 mol%. The mole percentage of Na2O in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.50 mol%, 1.0 mol%, 1.25 mol%, 2.0 mol%, 3.0 mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 10.0 mol%, 11.0 mol%, 12.0 mol%, or within any range bound by any two of those values (e.g., from 0 mol% to 1.25 mol%, from 2.0 mol% to 5.0 mol%, from 0 mol% to 12.0 mol%, and so on). The silica glass composition can be substantially free or free of Na2O. Further, the composition can be substantially free or free ofAttorney Docket No. SP24-152PCT any alkali metal oxide (R2O) and thus is substantially free or free of any alkali metal ions. As mentioned above, alkali metals can degrade silicon based solar cells and thus it can be advantageous to limit their inclusion in the composition.

[0094] In embodiments, the silica glass composition further includes lithium oxide, Li2O, as amodifier. The mole percentage of Li2O in these embodiments of the silica glass composition is within a range of from 0 mol% to 3.0 mol%. The mole percentage of Li2O in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.25 mol%, 0.50 mol%, 0.75 mol%, 1.0 mol%, 1.25 mol%, 1.5 mol%, 1.75 mol%, 2.0 mol%, 2.25 mol%, 2.5 mol%, 2.75 mol%, 3.0 mol%, 3.25 mol%, 3.5 mol%, 3.75 mol%, 4.0 mol%, 4.25 mol%, 4.5 mol%, 4.75 mol%, 5.0 mol%, 5.25 mol%, 5.5 mol%, 5.75 mol%, 6.0 mol%, 6.25 mol%, 6.5 mol%, 6.75 mol%, 7.0 mol%, or within any range bound by any two of those values (e.g., from 1.0 mol% to 2.0 mol%, from 0.25 mol% to 0.50 mol%, and so on). The composition can be substantially free or free of Li2O.

[0095] In embodiments, the sum of Na2O and Li2O in the silica glass composition can be withina range of from 0 mol% to 1.75 mol%. For example, the sum of Na2O and Li2O in the silica glass composition can be 0, greater than 0 mol%, 0.1 mol%, 0.2 mol%, 0.3 mol%, 0.4 mol%, 0.5 mol%, 0.6 mol%, 0.7 mol%, 0.8 mol%, 0.9 mol%, 1.0 mol%, 1.1 mol%, 1.2 mol%, 1.3 mol%, 1.4 mol%, 1.5 mol%, 1.6 mol%, 1.7 mol%, 1.75 mol%, or within any range bound by any two of those values (e.g., from 0.2 mol% to 1.3 mol%, from 0.3 mol% to 1.2 mol%, and so on).

[0096] For purposes of this disclosure, “R2O” is the sum of all alkali oxides of the silica glasscomposition. In embodiments, R2O + (BeO + MgO + CaO + SrO + BaO) - Al2O3 - B2O3 is from -50 mol% to 10 mol% of the silica glass composition. For example, R2O + (BeO + MgO + CaO + SrO + BaO) - Al2O3- B2O3can be -50 mol%, -45 mol%, -40 mol%, -35 mol%, -30 mol%, -25 mol%, -20 mol%, -15 mol%, -10 mol%, -5 mol%, 0 mol%, 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, or within any range bound by any two of those values (e.g., -25 mol% to 1 mol%, -25 mol% to 4 mol%, -50 mol% to 4 mol%, and so on). Similarly, in embodiments, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 – (MgO / 4) is within a range of from -50 mol% to 12 mol%. For example, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3– B2O3– (MgO / 4) can be -50 mol%, -40 mol%, -30 mol%, -20 mol%, -10 mol%, 0 mol%, 5 mol%, 10 mol%, 12 mol%, or within any range bound by any two of those values (e.g., from -30 mol% to 0 mol%, from -10 mol% to 5 mol%, and so on)Attorney Docket No. SP24-152PCT

[0097] In connection with this disclosure, it has been found that the best QY can be obtainedwhen the excess modifiers expressed as R2O+RO−Al2O3−B2O3 is less than 3 and preferably less than 0. Thus, compositions with more Al2O3+B2O3 than R2O+RO are desirable.

[0098] In embodiments, the silica glass composition further includes lanthanum oxide, La2O3,as a modifier of the composition. The mole percentage of La2O3 in these embodiments of the silica glass composition is within a range of from 0 mol% to 20 mol%. The mole percentage of La2O3in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.50 mol%, 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, 16 mol%, 17 mol%, 18 mol%, 19 mol%, 20 mol%, or within any range bound by any two of those values (e.g., from 1 mol% to 11 mol%, from 2 mol% to 15 mol%, and so on). The silica glass composition can be substantially free or free of La2O3. Lanthanides are useful for increasing the modulus of glass, but some lanthanides such as Pr, Nd, Sm, Tb, Dy, Ho, Er, Tm and Yb can absorb light and degrade the performance of the photon shifting solar glass and thus it is desirable to limit their concentration. In embodiments, the silica glass composition includes less than 0.5 mol% of a sum of La2O3, Y2O3, Pr2O3, Nd2O3, Tm2O3, Er2O3, Ho2O3, Lu2O3. In embodiments, the sum of La2O3, Y2O3, Pr2O3, Nd2O3, Tm2O3, Er2O3, Ho2O3, Lu2O3in the silica glass composition is 0 mol%, greater than 0 mol%, 0.1 mol%, 0.2 mol%, 0.3 mol%, 0.4 mol%, less than 0.5 mol%, 0.5 mol% or within any range bound by any two of those values (e.g., from 0 mol% to 0.1 mol%, and so on).

[0099] In embodiments, the silica glass composition further includes ferric oxide, Fe2O3, as amodifier. Fe2O3 is a ubiquitous contaminant in silica, alumina and other raw materials. While Fe2O3 absorbs UV light, it also can absorb visible light and also quench the fluorescence of Eu3+and Ce3+and so its concentration should be minimized as much as possible. The mole percentage of Fe2O3 in these embodiments of the silica glass composition is within a range of from 0 mol% to 0.1 mol%. The mole percentage of Fe2O3 in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.01 mol%, 0.02 mol%, 0.03 mol%, 0.04 mol%, 0.05 mol%, 0.06 mol%, 0.07 mol%, 0.08 mol%, 0.09 mol%, 0.1 mol%, or within any range bound by any two of those values (e.g., from 0 mol% to 0.03 mol%, from 0.01 mol% to 0.05 mol%, from 0.02 mol% to 0.06 mol%, from 0 mol% to 0.05 mol%, and so on). The silica glass composition can be substantially free or free of Fe2O3.

[0100] In embodiments, the silica glass composition further includes titanium dioxide, TiO2,as a modifier. TiO2 is a common contaminant in sand and other raw materials. When melted under reducing conditions such as those required to obtain Eu2+and Ce3+, Ti3+ions are formedAttorney Docket No. SP24-152PCT which are strongly absorbing and degrade the photoluminescence QY. Thus, it is desirable to limit the TiO2 concentration to 0.30% or less. The mole percentage of TiO2 in these embodiments of the silica glass composition is within a range of from 0 mol% to 0.30 mol%. The mole percentage of TiO2in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.01 mol%, 0.02 mol%, 0.03 mol%, 0.04 mol%, 0.05 mol%, 0.06 mol%, 0.07 mol%, 0.08 mol%, 0.09 mol%, 0.10 mol%, 0.11 mol%, 0.12 mol%, 0.13 mol%, 0.14 mol%, 0.15 mol%, 0.16 mol%, 0.17 mol%, 0.18 mol%, 0.19 mol%, 0.20 mol%, 0.21 mol%, 0.22 mol%, 0.23 mol%, 0.24 mol%, 0.25 mol%, 0.26 mol%, 0.27 mol%, 0.28 mol%, 0.29 mol%, 0.30 mol%, or within any range bound by any two of those values (e.g., from 0 mol% to 0.1 mol%, from 0.01 mol% to 0.05 mol%, from 0.02 mol% to 0.06 mol%, from 0 mol% to 0.25 mol%, and so on). The silica glass composition can be substantially free or free of TiO2.

[0101] In embodiments, the silica glass composition further includes lead monoxide, PbO,as a modifier. The mole percentage of PbO in these embodiments of the silica glass composition is within a range of from 0 mol% to 1.0 mol%. The mole percentage of PbO in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.01 mol%, 0.02 mol%, 0.03 mol%, 0.04 mol%, 0.05 mol%, 0.06 mol%, 0.07 mol%, 0.08 mol%, 0.09 mol%, 0.1 mol%, 0.2 mol%, 0.3 mol%, 0.4 mol%, 0.5 mol%, 0.6 mol%, 0.7 mol%, 0.8 mol%, 0.9 mol%, 1.0 mol%, or within any range bound by any two of those values (e.g., from 0.01 mol% to 0.05 mol%, from 0.02 mol% to 0.08 mol%, from 0 mol% to 0.1 mol%, and so on). The silica glass composition can be substantially free or free of PbO.

[0102] In embodiments, the silica glass composition further includes arsenic trioxide, As2O3,as a modifier. As2O3 is a commonly used to refine glass and eliminate small bubbles or “seeds,” but it can be desirable to limit its concentration. The mole percentage of As2O3in these embodiments of the silica glass composition is within a range of from 0 mol% to 0.1 mol%. The mole percentage of As2O3 in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.01 mol%, 0.02 mol%, 0.03 mol%, 0.04 mol%, 0.05 mol%, 0.06 mol%, 0.07 mol%, 0.08 mol%, 0.09 mol%, 0.1 mol%, or within any range bound by any two of those values (e.g., from 0.01 mol% to 0.05 mol%, from 0.02 mol% to 0.08 mol%, and so on). The silica glass composition can be substantially free or free of As2O3.

[0103] In embodiments, the sum of Sb2O3, Yb2O3, and Y2O3 in the silica glass compositionis within a range of from 0 mol% to 0.4 mol%. The total mole percentage of Sb2O3, Yb2O3, and Y2O3 in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.01 mol%, 0.02 mol%, 0.04 mol%, 0.05 mol%, 0.1 mol%, 0.2 mol%, 0.3 mol%, orAttorney Docket No. SP24-152PCT within any range bound by any two of those values (e.g., from 0.01 mol% to 0.05 mol%, from 0.02 mol% to 0.2 mol%, and so on). The silica glass composition can be substantially free or free of any or all of Sb2O3, Yb2O3, and Y2O3.

[0104] In embodiments, the silica glass composition further includes zirconia, ZrO2, as amodifier. ZrO2 improves the durability of silicate glasses but can degrade the liquidus temperature of the glass when its concentration exceeds about 4 mol%. The mole percentage of ZrO2in these embodiments of the silica glass composition is within a range of from 0 mol% to 4.0 mol%. The mole percentage of ZrO2 in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.01 mol%, 0.05 mol%, 0.10 mol%, 0.25 mol%, 0.50 mol%, 0.75 mol%, 1 mol%, 1.25 mol%, 1.50 mol%, 1.75 mol%, 2 mol%, 2.25 mol%, 2.50 mol%, 2.75 mol%, 3.00 mol%, 3.25 mol%, 3.50 mol%, 3.75 mol%, 4.0 mol%, or within any range bound by any two of those values (e.g., from 0.25 mol% to 2.50 mol%, from 0.75 mol% to 3 mol%, and so on). The silica glass composition can be substantially free or free of ZrO2.

[0105] In embodiments, the silica glass composition further includes zinc oxide, ZnO, as amodifier. The mole percentage of ZnO in these embodiments of the silica glass composition is within a range of from 0 mol% to 3 mol%. The mole percentage of ZnO in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.25 mol%, 0.50 mol%, 0.75 mol%, 1 mol%, 1.25 mol%, 1.5 mol%, 1.75 mol%, 2 mol%, 2.25 mol%, 2.5 mol%, 2.75 mol%, 3 mol%, or within any range bound by any two of those values (e.g., from 1 mol% to 2 mol%, from 0.25 mol% to 0.50 mol%, and so on). The silica glass composition can be substantially free or free of ZnO.

[0106] In embodiments, the silica glass composition further includes fluorides as a modifiersince it is effective at reducing viscosity, digesting SiO2, and tuning glass properties. The mole percentage of F in these embodiments of the composition is within a range of from 0 mol% to 0.5 mol%. The mole percentage of F in these embodiments of the silica glass composition can be 0 mol%, greater than 0 mol%, 0.05 mol%, 0.10 mol%, 0.15 mol%, 0.20 mol%, 0.25 mol%, 0.30 mol%, 0.35 mol%, 0.40 mol%, 0.45 mol%, 0.5 mol%, or within any range bound by any two of those values (e.g., from 0.05 mol% to 0.20 mol%, from 0.15 mol% to 0.30 mol%, and so on). The silica glass composition can be substantially free or free of F.

[0107] In embodiments, the silica glass composition further includes silver oxide, Ag2O, asa modifier. The mole percentage of Ag2O in these embodiments of the silica glass composition is within a range of from 0 mol% to 0.1 mol%. The mole percentage of Ag2O in these embodiments of the composition can be 0 mol%, greater than 0 mol%, 0.01 mol%, 0.02 mol%,Attorney Docket No. SP24-152PCT 0.03 mol%, 0.04 mol%, 0.05 mol%, 0.06 mol%, 0.07 mol%, 0.08 mol%, 0.09 mol%, 0.1 mol%, or within any range bound by any two of those values (e.g., from 0.01 mol% to 0.08 mol%, from 0.02 mol% to 0.05 mol%, and so on). The composition can be substantially free or free of Ag2O. Ag2O will reduce to Ag metal with the conditions required to make divalent Eu and trivalent Ce, thus it may be desirable to eliminate Ag2O from the glass.

[0108] In embodiments, the composition is substantially free or free of terbium, any terbiumoxide, and ions of terbium. The composition, however, can include a terbium oxide and / or ions of terbium.

[0109] In embodiments, divalent Eu ions (Eu2+ ions) are present as a phosphor constituentof the silica glass composition. In embodiments, the mole percentage of a sum of EuO and Eu2O3in the silica glass composition of the present disclosure is within a range of from greater than 0 mol% to 1.0 mol%. The mole percentage of the sum of EuO and Eu2O3 in these embodiments of the composition can be greater than 0 mol%, 0.0025 mol%, 0.005 mol%, 0.010 mol%, 0.025 mol%, 0.05 mol%, 0.075 mol%, 0.10 mol%, 0.125 mol%, 0.150 mol%, 0.17 mol%, 0.175 mol%, 0.20 mol%, 0.225 mol%, 0.250 mol%, 0.275 mol%, 0.30 mol%, 0.325 mol%, 0.350 mol%, 0.375 mol%, 0.40 mol%, 0.425 mol%, 0.450 mol%, 0.475 mol%, 0.48 mol%, 0.5 mol%, 0.6 mol%, 0.7 mol%, 0.8 mol%, 0.9 mol%, 1.0 mol%, or within any range bound by any two of those values (e.g., from 0.0025 mol% to 0.5 mol% from 0.05 mol% to 0.350 mol%, from 0.20 mol% to 0.375 mol%, from 0 mol% to 0.48 mol%, from 0.0025 mol% to 1.0 mol%, from 0.005 mol% to 0.17 mol%, from 0.010 mol% to 1.0 mol%, from 0.0025 mol% to 0.5 mol%, and so on). The silica glass composition can be substantially free of, or free of, EuO and Eu2O3. At high concentrations, the Eu2+QY can suffer as demonstrated by examples 43 through 45, so for best QY it is desirable to keep the concentration below 0.2 mol% expressed as Eu2O3or below 0.4 mol% expressed as EuO.

[0110] In embodiments, when the composition includes Eu2+ ions, the composition can besubstantially free or free of cerium, any cerium oxide, and ions of cerium. The composition, however, can include a cerium oxide and / or ions of cerium in addition to Eu2+ions.

[0111] Eu ions are typically batched (and expressed) as the stable Europium(III) oxide,Eu2O3. However, a reducing agent can be added with the batch to convert the Eu3+to Eu2+ions that are present in the resulting silica glass composition. The reducing agent can be a source of carbon. Sources of carbon include oils, sugar, cornstarch, coconut shells, graphite, amongothers, are reducing species that can reduce the Eu3+ to Eu2+ ions via Eu2O3+ ½C ^ 2EuO +½CO2 . In embodiments, the silica glass composition is a product of mixing, melting, andAttorney Docket No. SP24-152PCT forming the glass sheet from a batch composition that includes from greater than mol% 0 to 0.60 mol% of a reducing agent, such as carbon (C). Metallic reducing agents such as Si, Al, Mg, etc, or nitrides such as Si3N4, AlN, BN, etc can also be used to convert the Eu3+to Eu2+ions that are present in the resulting silica glass composition. Metals and nitrides are dense and sink to the bottom of silicate melts and can be very aggressive towards some commonly used refractory materials and degrade tank life. Thus, it is preferrable to use carbonaceous reducing agents (such as oils, sugar, cornstarch, coconut shells, graphite) that float on silicate melts and are not as aggressive towards common glass tank refractories.

[0112] While Eu3+ ions do absorb in the UV, the absorbance is orders of magnitude weakerand narrower than Eu2+which has much stronger and broader absorption. A mix of the two oxidization states can also be used, but for the highest quantum yield it is desirable to convert as much Eu to the divalent state as possible to avoid parasitic Eu2+to Eu3+charge transfer which absorbs but does not efficiently emit light and degrades performance. Eu is found predominantly as Eu3+in most glasses so is typically expressed as Eu2O3equivalents in the prior art.

[0113] In embodiments, trivalent Ce ions (Ce3+ ions) are present as a phosphor constituentof the silica glass composition. The combined mole percentage of Ce2O3and CeO2in these embodiments of the composition is within a range of from greater than 0 mol% to 0.5 mol%. The mole percentage of Ce2O3 and CeO2 in these embodiments of the composition can be 0.01 mol%, greater than 0.01 mol%, 0.020 mol%, 0.025 mol%, 0.04 mol%, 0.05 mol%, 0.075 mol%, 0.10 mol%, 0.125 mol%, 0.150 mol%, 0.175 mol%, 0.20 mol%, 0.225 mol%, 0.250 mol%, 0.275 mol%, 0.30 mol%, 0.325 mol%, 0.350 mol%, 0.375 mol%, 0.40 mol%, 0.425 mol%, 0.450 mol%, 0.475 mol%, 0.5 mol%, or within any range bound by any two of those values (e.g., from 0.05 mol% to 0.5 mol%, from 0.05 mol% to 0.350 mol%, from 0.20 mol% to 0.375 mol%, from 0.01 mol% to 0.5 mol%, from 0.020 to 0.5, from 0.04 to 0.350, and so on). The silica glass composition can be substantially free of, or free of, Ce2O3 and CeO2. At high concentrations the Ce3+QY can suffer as shown by examples 30 and 31, so it is desirable to keep the Ce concentration below about 0.3 expressed as mol% Ce2O3 or below 0.6 when expressed as mol% CeO2 for highest QY.

[0114] Ce is also multivalent and can be present as Ce4+ (CeO2) or Ce3+ ions in the glass.While a combination of the two oxidation states creates the highest absorption via charge transfer, it does not efficiently emit light. For maximal conversion of UV photons to visible photons it is desirable to have as much Ce converted to the trivalent ion as possible since Ce3+can convert UV to visible photons with >90% QY. The same reducing agents used for Eu canAttorney Docket No. SP24-152PCT be used for Ce. For example, carbon can be used to reduce any CeO2to Ce2O3via 2CeO2+ ½C ^ Ce2O3 + ½CO2. Ce is commonly expressed as CeO2 and Ce2O3 since both are common in most glasses unless special effort is made to control the redox state. In embodiments, the silica glass composition is a product of mixing, melting, and forming the glass sheet from a batch composition that includes from greater than mol% 0 to 0.60 mol% a reducing agent, such as carbon (C).

[0115] In embodiments, when the composition includes Ce3+ ions, the composition can besubstantially free or free of europium, any europium oxide, and ions of europium. The composition, however, can include a europium oxide and / or ions of europium in addition to Ce3+ions.

[0116] In embodiments, Al2O3 / (Eu2O3 + Ce2O3 + CeO2 / 2) is greater than or equal to 3.5mol% of the silica glass composition for high QY.

[0117] In more particular embodiments, the glass composition includes from 61 mol% to 88mol% SiO2, from 0.05 mol% to 30 mol% Al2O3, and from greater than 0 mol% to 0.48 mol% Eu2O3. In other more particular embodiments, the glass composition includes from 60 mol% to 75 mol% SiO2, from 0.3 mol% to 20 mol% Al2O3, and from 0.025 mol% to 0.5 mol% Ce2O3. In other more particular embodiments, the glass composition includes from 55 mol% to 88 mol% SiO2, from 0.0025 mol% to 0.5 mol% Eu2O3, and 0.05 mol% to 0.5 mol% Ce2O3.

[0118] In embodiments, the glass sheet 10 (when the thickness 16 is 0.7 mm) exhibits aphotoluminescence peak emission wavelength within a range of from 425 nm to 475 nm when excited with electromagnetic radiation having a wavelength of 350 nm. The photoluminescence peak emission wavelength can be 425 nm, 430 nm, 435 nm, 440 nm, 445 nm, 450 nm, 455 nm, 460 nm, 465 nm, 470 nm, 475 nm, or within any range bound by any two of those values (e.g., from 430 nm to 440 nm, from 430 nm to 435 nm).

[0119] In embodiments, the glass sheet 10 both (i) when excited with electromagneticradiation having a wavelength of 290 nm and (ii) when excited separately with electromagnetic radiation having a wavelength of 350 nm, exhibits in both cases a photoluminescence quantum yield of greater than 75%. The photoluminescence quantum yield that the glass sheet 10 exhibits when excited with electromagnetic radiation having a wavelength of 290 nm can be greater than 60%, 75%, 80%, 85%, 90%, 95%, 99.9%, or within any range bound by any two of those values (e.g., from 80% to 85%, from 80% to 95%, and so on). The photoluminescence quantum yield that the glass sheet 10 exhibits when excited with electromagnetic radiation having a wavelength of 350 nm can be greater than 60%, 75%, 80%, 85%, 90%, 95%, 99.9%,Attorney Docket No. SP24-152PCT or within any range bound by any two of those values (e.g., from 80% to 85%, from 80% to 95%, and so on). Further, of the photoluminescent electromagnetic radiation that the glass sheet 10 exhibits when so excited by the wavelengths of 290 nm and separately 350 nm, greater than 75% of the photoluminescent electromagnetic radiation has a wavelength greater than 400 nm.

[0120] Referring now to FIGS. 2-5, a solar panel 100 includes the glass sheet 10 and one ormore photovoltaic cells 102. The glass sheet 10 is positioned relative to the one or more photovoltaic cells 102 such that electromagnetic radiation transmits through the glass sheet 10 and impinges upon the one or more photovoltaic cells 102. In embodiments, the array of photovoltaic cells 102 is disposed beneath the second primary surface 14 of the glass sheet 10. The glass sheet 10 separates the array of photovoltaic cells 102 from an external environment 104. The first primary surface 12 of the glass sheet 10 faces the external environment 104. The first primary surface 12 of the glass sheet 10 is intended to face the Sun 106, such as during daytime hours. The second primary surface 14 of the glass sheet 10 faces the array of photovoltaic cells 102. During use of the solar panel 100, photons 108 from the Sun 106 enter the solar panel 100 through the glass sheet 10 and impinge upon the one or more photovoltaic cells 102. The type of photovoltaic cells 102 are not particularly limited, though in preferred embodiments, the photovoltaic cells 102 are monocrystalline silicon photovoltaic cells 102.

[0121] In embodiments, the solar panel 100 further includes a backsheet 110. The one ormore photovoltaic cells 102 are disposed between the glass sheet 10 and the backsheet 110. The backsheet 110 can have a glass composition. The glass composition of the backsheet 110 can be the same as the composition of the glass sheet 10 but need not be. One glass sheet 10 of the present disclosure can be the glass sheet 10 of the solar panel 100 and another glass sheet 10 of the present disclosure can be the backsheet 110 of the solar panel 100.

[0122] Having the one or more photovoltaic cells 102 sandwiched between the glass sheet10 and the backsheet 110 having a glass composition allows the array of photovoltaic cells 102 to receive photons 108 transmitting through both the glass sheet 10 and the backsheet 110. That arrangement in theory should increase the electricity production of the solar panel 100 compared to if the array of photovoltaic cells 102 received photons 108 transmitting only through the glass sheet 10 but not the backsheet 110.

[0123] A first polymer layer 112 can be disposed between the glass sheet 10 and the arrayof photovoltaic cells 102. Similarly, a second polymer layer 114 can be disposed between the backsheet 110 and the array of photovoltaic cells 102. The first and second polymer layers 112, 114 can further reduce migration of ions (e.g., K+) from the glass sheet 10 and theAttorney Docket No. SP24-152PCT backsheet 110 (e.g., further in addition to the glass sheet 10 already not having the more mobile Li+and Na+ions), respectively, to the photovoltaic cells 102 that could cause potential-induced degradation, which is degradation of the photovoltaic cells 102 that lowers efficiency thereof. The first and second polymer layers 112, 114 can be formed of a transparent polymer, such as ethylene-vinyl acetate (EVA). The first and second polymer layers 112, 114 can encapsulate the one or more photovoltaic cells 102.

[0124] In embodiments, the solar panel 100 further includes a frame 116. When the solarpanel 100 is oriented horizontally such that the first primary surface 12 of the glass sheet 10 is horizontal and facing upwards, the frame 116 defines a top 118 and a bottom 120 of the solar panel 100 where the top 118 is most elevated portion of the solar panel 100 and the bottom 120 is the least elevated portion of the solar panel 100, excluding wiring that may extend from the solar panel 100. In a more detailed example, the frame 116 includes sidewall 122, a C-channel 124 that is contiguous with the sidewall 122, and a tab 126 that extends inward relative to the sidewall 122. The C-channel 124 is disposed at or near the top 118 of the frame 116, and the tab 126 is disposed at or near the bottom 120 of the frame 116. The tab 126 forms a plane 128 that is generally parallel to an outward primary surface 130 of the backsheet 110. The glass sheet 10, the one or more photovoltaic cells 102, and the backsheet 110 are all coupled to each other as a package 132. The sidewall 122 extends around a perimeter 134 of the package 132 with the perimeter 134 of the package 132 secured within the C-channel 124 of the frame 116.

[0125] The glass sheet 10 of the present disclosure addresses the problems mentioned in theBackground, in a variety of ways. Among them, the glass sheet 10 absorbs a substantial percentage of photons 108 from the Sun 106 associated with the ultraviolet range of electromagnetic radiation compared to prior efforts. Without being bound by theory the improved absorbance can be attributed to not only the presence of either Eu2O3or Ce2O3, or both Eu2O3 and Ce2O3, but additionally to (i) a limitation on the mole percentage of other modifiers of glass structure forming the glass sheet 10, (ii) the inclusion during batching of a reducing agent to cause the cerium, when present in the composition of the glass sheet 10, to take Ce3+ionic sate rather than Ce4+ionic state, and (iii) the inclusion during batching of the reducing agent to push europium, when present in the composition, to take the Eu2+ionic state rather than some other ionic state (e.g., Eu3+). The ionic state of Ce4+causes parasitic charge transfer between Ce3+and Ce4+, which decreases the photoluminescence quantum yield. Similarly, the ionic state of europium other than Eu2+again leads to parasitic charge transfer and decreased photoluminescence quantum yield. Further, the UV absorption cut off can be tuned by changing the concentration of Ce3+and Eu2+, or using a combination of the two,Attorney Docket No. SP24-152PCT without decreasing the photoluminescence quantum yield. The absorption of such ultraviolet light reduces or prevents forms of damage to the one or more photovoltaic cells 102 that would have otherwise occurred and darkening of the encapsulant(s).

[0126] Further, instead of entirely releasing the energy from the absorbed photons 108 in theform of heat, which degrades solar cell efficiency and could cause other forms of damage to the one or more photovoltaic cells 102, the glass sheet 10 releases some of the energy from the absorbed photons 108 as visible light. Notably, the inclusion of Ce3+increases absorption at shorter ultraviolet wavelengths and transfers the absorbed energy to Eu2+, which then emits the energy as visible light that the one or more photovoltaic cells 102 can utilize to generate electrical current. The release of the visible light is additionally beneficial because the one or more photovoltaic cells 102 can utilize the released visible light to generate electrical current. That increases the efficiency of the solar panel 100 as a whole.

[0127] In addition, various embodiments of the composition are free of or substantially freeof any alkali metal oxide or ions of alkali metals.

[0128] Further, various embodiments of the glass sheet 10 are fusion formable. The generalprinciples of fusion formation are known by those of ordinary skill in the art. By being fusion formable, the glass sheet 10 need not be formed via a float-glass process. As a result, the glass sheet 10 can be formed with the thickness 16 being relatively thin, which reduces weight of the glass sheet 10 and the solar panel 100 overall.

[0129] EXAMPLES

[0130] Examples 1-65 – For Examples 1-65, batches were made according to the molepercentages in the tables that follow, and glass sheets made therefrom. It is expected that glass sheets made pursuant to the batched compositions will exhibit a composition, as analyzed, that is substantially similar if not identical to the batched composition (except for fugitive reducing agents such as C which will consume oxygen and leave as gaseous CO2 and CO so little to no C will be left in the glass after melting). Several photoluminescence properties were then measured for each of the glass sheets. The compositions as batched and the results of the measurements are reproduced in Tables 1-3 below. Constituent values are in mole percentage. It should be noted that in the batched compositions, Al2 and Al2N2 can be considered to be a direct replacement of Al2O3, Na2F2can be considered to be a direct replacement of Na2O, and CaF2can be considered to be a direct replacement of CaO.

[0131] Glasses were made by mixing the appropriate raw materials and melting in fusedquartz crucibles with silica lids at a temperature between 1400 and 1650° for 4 to 7 hours. The lids were removed and the glass was poured onto a steel plate and then annealed for 2 hours.Attorney Docket No. SP24-152PCT Test samples were then cut, ground, and polished from the annealed glass patties. Examples 28-31 and 64-65 were made by infiltrating porous Vycor® plates with an aqueous solution of aluminum chloride and europium or cerium nitrate overnight. The infiltrated samples were then dried at 80°C overnight and consolidated in a nitrogen atmosphere tube furnace at 1050°C for 4 hours. Example 65 was consolidated in a 4% H2 96%N2 atmosphere to get better reduction of Eu3+to Eu2+.

[0132] “Peak Emission (290nmEx)” refers to the wavelength (in nm) associated with thepeak of emitted electromagnetic radiation after being excited with electromagnetic radiation having a wavelength of 290 nm. Similarly, “Peak Emission (350nmEx)” refers to the wavelength associated with the peak of emitted electromagnetic radiation after being excited with electromagnetic radiation having a wavelength of 350 nm. “QY 290 Ex” refers to the photoluminescence quantum yield after being excited with electromagnetic radiation having a wavelength of 290 nm. “QY 350 Ex” refers to the photoluminescence quantum yield after being excited with electromagnetic radiation having a wavelength of 350 nm.

[0133] A limited set of the glass superstrates were tested in experimental modules asdescribed below for the specific case of Example 52. Of those tested, Examples 50, 52, and 69-73 improved the short-circuit current by greater than 1% relative to modules formed with commercial soda lime glass of identical thickness. It is possible that other compositions would provide similar measured improvements. Generally, the results will depend on the specific materials used to form the modules.

[0134] The compositions of all of Examples 1-31 include Ce2O3 but not Eu2O3.Attorney Docket No. SP24-152PCTAttorney Docket No. SP24-152PCT

[0135] The compositions of all of Examples 32-65 include Eu2O3 but not Ce2O3. Thecompositions and property values are set forth in Table 2 below.Attorney Docket No. SP24-152PCTAttorney Docket No. SP24-152PCT

[0136] The compositions of all of Examples 66-74 include both Eu2O3 and Ce2O3. Thecompositions and property values are set forth in Table 3 below.Attorney Docket No. SP24-152PCT

[0137] The compositions of Examples 75-85 all include Eu2O3, with only Example 85further including CeO2. The compositions and property values are set forth in Table 4 below.Attorney Docket No. SP24-152PCT

[0138] For all of Examples 1-74, the quantum yield as a function(Li2O+Na2O+K2O+CaO+SrO+BaO)-Al2O3-B2O3was plotted. The graph is reproduced in FIG. 6. Review of the graph shows that a photoluminescence quantum yield of greater than 50% could only be achieved when (Li2O+Na2O+K2O+CaO+SrO+BaO)-Al2O3-B2O3 was less than 4 mol%. When (Li2O+Na2O+K2O+CaO+SrO+BaO)-Al2O3-B2O3was less than 4 mol%, then photoluminescence quantum yields of greater than 90% were possible both when excited with electromagnetic radiation having a wavelength of 290 nm and when excited with electromagnetic radiation having a wavelength of 350 nm. Notably, MgO is excluded from the relationship (Li2O+Na2O+K2O+CaO+SrO+BaO)-Al2O3-B2O3because Examples 38 (176CNZ) through 44 (176COF) reveal that even glass sheets with relatively high MgO content still exhibit relatively high photoluminescence quantum yield. This is because MgO can act as a modifier or an intermediate as discussed earlier.Attorney Docket No. SP24-152PCT

[0139] There are examples revealed in the graph of FIG. 6 that satisfy(Li2O+Na2O+K2O+CaO+SrO+BaO)-Al2O3-B2O3 being less than 4 mol% but still have a photoluminescence quantum yield of less than 50%. It is believed that is so because the glass sheet was either too oxidized or too reduced. When the glass sheet is batched from a composition that includes insufficient reducing agents (such as carbon), some of the Ce will be Ce3+and some will be Ce4+, which results in higher absorption of ultraviolet light due to electrons being excited from Ce3+to Ce4+but does not result in useful photoluminescence and instead just generates heat. The same happens with mixed oxidation states of Eu. Example 25 is an instance where sufficient reducing agent was added (0.25 mole percent carbon), and the photoluminescence quantum yield is relatively high at 96% after excitation at 290 nm. However, if too much reducing agent is added, then the glass formers themselves can be reduced and turn the glass sheet dark which destroys solar panel efficiency. For this reason, it is also important to keep transition metal contamination very low, otherwise they are easily reduced and darken the glass sheet. During formation of the glass sheet from the batched composition, the carbon is release into the atmosphere as carbon dioxide and does not appear in the glass sheet composition as analyzed.

[0140] For Examples 53-56, which all include Eu2O3 but not Ce2O3, the wavelengthassociated with the peak emission after being excited at 350 nm and photoluminescence quantum yield were plotted as a function of the mole percentage of CaO+SrO−Al2O3−B2O3. The graph is reproduced in FIG. 7. Review of the graph shows that photoluminescence quantum yield decreases, and the wavelength of peak emission increases, as CaO+SrO−Al2O3−B2O3 increases. Thus, there is a tradeoff between larger wavelength shift and good efficiency (QY).

[0141] For Examples 50-52 (including Eu2O3 but not Ce2O3) and Examples 68-73 (includingboth Eu2O3 and Ce2O3), the glass sheets were formed to have a thickness of 0.69 mm. The percentage transmission as a function of wavelength throughout the range of from 200 nm to 500 nm was determined. The results were then plotted. A typical solar panel soda lime glass cover having a thickness of 2.0 mm was also analyzed in the same manner and plotted as a comparative example. The results are reproduced in the graph in FIG. 8. Most of those examples transmit less than 20% of wavelengths shorter than about 340 nm, which can slow degradation of the one or more photovoltaic cells by a factor of five. It is believed that Eu2O3is present within those Examples as Eu2+, because Eu3+absorbs very little and thus the absorption must be attributable to the presence of Eu2+. The Examples plotted on FIG.8 show that the combination of Ce3+and Eu2+can successfully absorb ultraviolet light havingAttorney Docket No. SP24-152PCT wavelengths throughout the range of from 325 nm to 375 nm compared to the soda lime glass comparative example. While Eu2+has a more favorable emission spectrum than Ce3+for conversion to electrical current by the one or more photovoltaic cells, Eu2O3 is more expensive than Ce2O3. When both Eu2O3and Ce2O3are included in the composition, the range of ultraviolet wavelengths absorbed is broadened, and Ce3+ions can transfer the absorbed energy to Eu2+ion, which can then emit electromagnetic radiation in a red-shifted manner usable by the one or more photovoltaic cells. The plots of FIG. 8 show that increasing the Eu2O3concentration while Ce2O3 remains constant increases absorption of ultraviolet light closer to the visible spectrum.

[0142] For Examples 50-52 (including Eu2O3 but not Ce2O3), excitation spectra andemission spectra were determined and reproduced in the graph of FIG. 9. For the excitation spectra, shown toward the left of the graph, the emission intensity for each of the glass sheets was measured at 450 nm as a function of the wavelength of the exciting light. For the emission spectra, shown toward the bottom and right of the graph, the glass sheets were each excited with electromagnetic radiation having wavelengths of 300 nm and then 380 nm, in separate sessions, and the photoluminescence intensity in response to the excitation was then measured as a function of wavelength of the photoluminescent emission. Review of the graph shows that increasing Eu2+concentration increases absorption of ultraviolet electromagnetic radiation, as evidenced by increased photoluminescent emission intensity at 450 nm. Similarly, when exciting at 300 nm or 380 nm, the photoluminescent emission increases with increasing Eu2+concentration.

[0143] Current-voltage (JV) characteristics were determined for bare polycrystalline Siphotovoltaic cells, soldered cells, and solar modules made with (a) 0.69 mm thick solar panel soda lime glass cover and (b) 0.69 mm thick cover glass sheet of Example 52. Each curve is the average of those measured for three cells and two cells for the soda lime glass and Example 52, respectively. Example 52 was chosen because that glass sheet exhibited the strongest absorption of ultraviolet light of those plotted at FIG. 8, in addition to a relatively high photoluminescence quantum yield (89.3%, see Table 2) and a peak emission wavelength well within the visible spectrum (434 nm when excited at 350 nm). The polycrystalline Siphotovoltaic cells had dimensions of 19 mm x 52 mm (for an area Acell of 9.88 cm2) and wereproduced by Aoshike Technology (Shenzhen, China). The current-voltage characteristics were measured under standard test conditions (25°C, 1 Sun irradiance, and an AM1.5G incident spectrum). The results for the solar soda lime glass cover are reproduced at FIG. 10A. The results for the glass sheet of Example 52 are reproduced at FIG.10B.Attorney Docket No. SP24-152PCT

[0144] As FIGS. 10A and 10B show, the polycrystalline Si photovoltaic cells exhibited ashort-circuit current density (Jsc = Isc / Acell, where Isc is the short-circuit current) and an open-circuit voltage (Voc) of ~35 mA cm-2and ~0.6 V, respectively. After soldering busbars to the negative (top) and positive (bottom) terminals of the polycrystalline Si photovoltaic cells, theIV curves were re-measured. The Jsc decreased about -2.1% and -2.8% in each set of samples.The decrease in Jsc is thought to be a consequence of the top busbar shading the photovoltaiccell.

[0145] The soldered cells were then formed into modules with the following stack layers:(1) the glass sheet cover, (2) evguard® UV-380 ethylene-vinyl acetate (EVA) encapsulant, (3) poly-Si solar cell, (4) evguard® UV-380 EVA encapsulant, and (5) DuPont Tedlar® TPTbacksheet. The JV curves were then remeasured. Although the soldered cells for bothexperiments had very similar short-circuit current densities of 33.89 mA cm-2and 34.05 mA cm-2, the solar modules employing soda lime glass and the glass sheet of Example 52 exhibited Jscvalues of 33.98 mA cm-2and 34.58 mA cm-2, respectively, as shown in FIGS.10A and 10B.Relative to the soldered cell, Jsc of the solar module with the glass sheet of Example 52 exhibitsa significant increase (+1.6 ± 0.3%) compared to the module with the commercial solar soda lime glass (+0.3 ± 0.4%). That means that the glass sheet of Example 52 provides an added relative improvement of ~1.3% compared to the soda lime glass cover substrate.

[0146] It is believed that the exhibited Jsc increased following the addition of the EVAencapsulant and the cover glass above the soldered cell, even in the module with commercial soda lime glass, because the encapsulant and cover glass trap light that the busbar and the photovoltaic cell would have scattered away and reduce the reflectance at the surface of the photovoltaic cell through improved index-matching with EVA (n ~ 1.48) instead of air (n ~ 1).

[0147] Comparative Example 1 – For Comparative Example 1, a glass sheet was batchedaccording to the mole percentage in the table below. Despite being formed from a batch including just 1 mol% TiO2, the resulting glass sheet exhibited a QY of less than 10%. That is in contrast to the glass sheets batched according to the mole percentages of Examples 75-85, which all exhibited a QY of at least 81.0 (for Example 83), despite being batched according to virtually identical compositions except for the lack of TiO2. The glass sheet batched according to the mole percentage listing of Comparative Example 1 was dark in color and the TiO2blocked the UV light and diminished the fluorescence.Attorney Docket No. SP24-152PCT

[0148] It will be apparent to those skilled in the art that various modifications and variationscan be made without departing from the spirit or scope of the claims.

Claims

Attorney Docket No. SP24-152PCT CLAIM(S) What is claimed is:

1. A glass sheet comprising:a silica glass composition comprising Eu2+ions, wherein, the glass sheet exhibits, at a thickness of 0.7 mm, (i) less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm, (ii) less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm, (iii) greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm, and (iv) a photoluminescence quantum yield of greater than 50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm.

2. The glass sheet of claim 1, whereinthe silica glass composition comprises (in mole percentage) from 60.0 to 99.5 SiO2.

3. The glass sheet of any one of claims 1-2, whereinthe silica glass composition comprises (in mole percentage): from 61 to 88 SiO2; from 0.05 to 30.0 Al2O3; from 0 to 25.0 B2O3; from 0 to 30.0 MgO; from 0 to 25.0 CaO; from 0 to 25.0 SrO; from 0 to 25.0 BaO; from 0 to 12.0 Na2O; and from 0 to 20 La2O3; wherein, R2O + (BeO + CaO + SrO + BaO) – Al2O3– B2O3is from -50 to 4 mol% of the glass composition, where R2O is the sum of all alkali oxides of the composition.

4. The glass sheet of claim 3, whereinthe silica glass composition comprises (in mole percentage): from 62.0 to 69.0 SiO2; from 12.0 to 22.0 Al2O3; and from 9.0 to 23.5 RO, wherein RO is the sum of MgO, CaO, SrO, BaO, and BeO.Attorney Docket No. SP24-152PCT5. The glass sheet of claim 4, whereinthe silica glass composition comprises (in mole percentage): from 10.0 to 20.0 MgO.

6. The glass sheet of claim 4, whereinthe silica glass composition comprises (in mole percentage): from 2.0 to 6.0 MgO; from 4.0 to 9.5 CaO; and from 0.25 to 4.5 SrO.

7. The glass sheet of any one of claims 4-6, whereinthe silica glass composition comprises (in mole percentage): from 5.0 to 12.0 B2O3.

8. The glass sheet of any one of claims 4-7, whereinin the silica glass composition, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3– B2O3 – (MgO / 4) is within a range of from -50 mol% to 12 mol%.

9. The glass sheet of any one of claims 4-8, whereinin the silica glass composition, (CaO + BaO) – Al2O3– B2O3is less than -11 mol%.

10. The glass sheet of any one of claims 1-9, whereinthe silica glass composition comprises (in mole percentage) from 0.0025 to 1.0 of a sum of Eu2O3 and EuO.

11. The glass sheet of claim 10, whereinthe silica glass composition comprises (in mole percentage) from 0.005 to 0.17 of the sum of Eu2O3 and EuO.

12. The glass sheet of any one of claims 1-11, whereinthe silica glass composition is substantially free of cerium, any cerium oxide, and ions of cerium.Attorney Docket No. SP24-152PCT13. The glass sheet of any one of claims 1-13, whereinthe silica glass composition is a product of mixing, melting, and forming the glass sheet from a batch composition that includes (in mole percentage): from greater than 0 to 0.60 a reducing agent.

14. A glass sheet comprising:a silica glass composition comprising Ce3+ions, wherein, the glass sheet exhibits, at a thickness of 0.7 mm, (i) less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm, (ii) less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm, (iii) greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm, and (iv) a photoluminescence quantum yield of greater than 50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm.

15. The glass sheet of claim 14, whereinthe silica glass composition comprises (in mole percentage) from 60.0 to 99.5 SiO2.

16. The glass sheet of claim 14, whereinthe silica glass composition comprises (in mol%): from 60.0 to 75.0 SiO2; from 0.30 to 20.0 Al2O3; from 0 to 25.0 B2O3; from 0 to 30.0 MgO; from 0 to 20.0 CaO; from 0 to 20.0 SrO; and from 0 to 20.0 BaO; wherein, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 is from -50 to 4 mol% of the glass composition, where R2O is the sum of all alkali oxides of the glass composition.

17. The glass sheet of claim 16, whereinthe silica glass composition comprises (in mol%): from 62.0 to 69.0 SiO2;Attorney Docket No. SP24-152PCT from 12.0 to 22.5 Al2O3; and from 11.5 to 22.5 RO, wherein RO is the sum of MgO, CaO, SrO, BaO, and BeO.

18. The glass sheet of any one of claims 16-17, whereinthe silica glass composition comprises (in mol%): from 10.0 to 23.0 MgO.

19. The glass sheet of any one of claims 16-18, whereinthe silica glass composition comprises (in mole percentage): from 5.0 to 12.0 B2O3.

20. The glass sheet of claim 16, whereinthe silica glass composition comprises (in mole percentage): from 65.0 to 75.0 SiO2; from 3.0 to 4.0 Al2O3; from 15.0 to 25.0 B2O3; >0 Li2O; >0 Na2O; and >0 CaO.

21. The glass sheet of any one of claims 16-20, whereinR2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 is from -25 to 4 mol% of the composition, where R2O is the sum of all alkali oxides of the glass composition.

22. The glass sheet of any one of claims 16-21, wherein(BeO + MgO + CaO + SrO + BaO) – Al2O3is from -25 to 15 mol% of the composition.

23. The glass sheet of claim 14, whereinthe silica glass composition further comprises (in mol%): from 60.0 to 69.9 SiO2; from 0.10 to 22.0 Al2O3; from 0 to 17.0 B2O3; from 0 to 1.75 of a sum of Li2O and Na2O;Attorney Docket No. SP24-152PCT from 0 to 0.05 Fe2O3; from 0 to 0.25 TiO2; from 0 to 1.0 PbO; and from 0 to 0.1 As2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 0.85 mol% of the composition.

24. The glass sheet of claim 14, whereinthe silica glass composition further comprises (in mol%): from 60.0 to 69.9 SiO2; from 0.10 to 22.0 Al2O3; from 0 to 25.0 B2O3; from 0 to 1.75 of a sum of Li2O and Na2O; from 0 to 0.05 Fe2O3; from 0 to 1.0 PbO; from 0 to 0.4 of a sum of Sb2O3, Yb2O3, and Y2O3; and from 0 to 0.1 As2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 0.85 mol% of the composition.

25. The glass sheet of claim 14, whereinthe silica glass composition further comprises (in mol%): from 60.0 to 75.0 SiO2; from 0.10 to 25.0 Al2O3; from 0 to 9.25 B2O3; from 0 to 1.0 BaO; from 0 to 1.75 of the sum of Li2O and Na2O; from 0 to 0.25 TiO2; from 0 to 1.0 PbO; and from 0 to 0.5 of a sum of La2O3, Y2O3, Pr2O3, Nd2O3, Tm2O3, Er2O3, Ho2O3, Lu2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 3.0 mol% of the composition.

26. The glass sheet of claim 25, whereinAttorney Docket No. SP24-152PCT the silica glass composition comprises (in mol%): from 0 to 3.0 B2O3; and from 0 to 0.1 of the sum of La2O3, Y2O3, Pr2O3, Nd2O3, Tm2O3, Er2O3, Ho2O3, Lu2O3; and (BeO + MgO + CaO + SrO + BaO) – Al2O3 is from -40 to 2.2 mol% of the composition.

27. The glass sheet of any one of claims 14-26, whereinthe silica glass composition further comprises (in mol%): from 0.025 to 0.5 of a sum of Ce2O3 and CeO2.

28. The glass sheet of claim 27, whereinthe silica glass composition comprises (in mol%): from 0.04 to 0.350 of the sum of Ce2O3 and CeO2.

29. The glass sheet of any one of claims 14-28, whereinthe silica glass composition is substantially free of europium, any europium oxide, and ions of europium.

30. The substrate of any one of claims 14-29, whereinthe silica glass composition is a product of mixing, melting, and forming the glass sheet from a batch composition that includes (in mole percentage): from greater than 0 to 0.60 of a reducing agent.

31. A glass sheet comprising:a silica glass composition comprising Eu2+ion and Ce3+ions, wherein, the glass sheet exhibits, at a thickness of 0.7 mm, (i) less than 50% transmission throughout an entirety of a wavelength range of from 200 nm to 360 nm, (ii) less than 20% transmission throughout an entirety of a wavelength range of from 250 nm to 340 nm, (iii) greater than 80% transmission throughout an entirety of a wavelength range of from 410 nm to 1200 nm, and (iv) a photoluminescence quantum yield of greater than 50% when excited with electromagnetic radiation having a wavelength within a range of from 280 nm to 370 nm.

32. The glass sheet of claim 31, whereinAttorney Docket No. SP24-152PCT the silica glass composition comprises (in mol%): from 55.0 to 88.0 SiO2; from 0 to 30.0 Al2O3; from 0 to 25.0 B2O3; from 0 to 30.0 MgO; from 0 to 20.0 CaO; from 0 to 20.0 SrO; and from 0 to 20.0 BaO; wherein, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 is from -50 to 4 mol% of the glass composition, where R2O is the sum of all alkali oxides of the glass composition.

33. The glass sheet of claim 32, whereinR2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3– B2O3is from -25 to 4 mol% of the glass composition.

34. The glass sheet of any one of claims 32-33, whereinthe silica glass composition comprises (in mol%): from 62.0 to 70.0 SiO2; from 10.0 to 20.0 Al2O3; from 4.0 to 10.0 B2O3; from 2.0 to 6.0 MgO; from 3.0 to 9.2 CaO; and from 0.30 to 4.5 SrO.

35. The glass sheet of claim 31, whereinthe silica glass composition comprises: from 61.0 to 99.5 SiO2; from 0.010 to 1.0 of the sum of Eu2O3 and EuO; and greater than 0.01 of the sum of Ce2O3and CeO2; and R2O + (BeO + CaO + SrO + BaO + ZnO) – Al2O3– B2O3is from -50 to 10 mol% of the silica glass composition, where R2O is the sum of all alkali oxides of the glass composition.

36. The glass sheet of claim 31, whereinAttorney Docket No. SP24-152PCT the silica glass composition comprises: from 61.0 to 99.95 SiO2; from 0 to 12.5 Na2O; from 0.005 to 0.17 of the sum of Eu2O3and EuO; from 0 to 0.05 Fe2O3; from 0 to 0.30 TiO2; from 0 to 4.0 ZrO2; and greater than 0 of the sum of Ce2O3 and CeO2; and Al2O3 / (Eu2O3 + Ce2O3 + CeO2 / 2) is greater than or equal to 3.5 mol% of the silica glass composition.

37. The glass sheet of any one of claims 31-36, whereinthe silica glass composition further comprises: from 0.0025 to 0.5 of the sum of Eu2O3and EuO; and from 0.020 to 0.5 of the sum of Ce2O3 and CeO2.

38. The glass sheet of any one of claims 31-37, whereinthe silica glass composition is substantially free of terbium, any terbium oxide, and ions of terbium.

39. The glass sheet of any one of claims 31-38, whereinthe silica glass composition is a product of mixing, melting, and forming the glass sheet from a batch composition that includes (in mole percentage): from greater than 0 to 0.60 of a reducing agent.

40. A glass sheet comprising:a silica glass composition comprising (in mol%): from 61.0 to 88.0 SiO2; greater than or equal to 0.05 Al2O3; from 0 to 12.5 Na2O; from 0.005 to 0.5 of a sum of Eu2O3and EuO; from 0 to 0.3 TiO2; and from 0 to 4.0 ZrO2;Attorney Docket No. SP24-152PCT wherein, in the silica glass composition, R2O + (BeO + MgO + CaO + SrO + BaO) – Al2O3 – B2O3 – (MgO / 4) is within a range of from -50 mol% to 4.5 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.

41. A glass sheet comprising:a silica glass composition comprising (in mol%): from 60.0 to 69.9 SiO2; from 0.1 to 22.0 Al2O3; from 0 to 17.0 B2O3; from 0.04 to 0.35 of a sum of Ce2O3and CeO2; from 0 to 0.05 Fe2O3; from 0 to 0.25 TiO2; from 0 to 1.0 PbO; and from 0 to 0.1 As2O3; wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3 is within a range of from -40 mol% to 0.85 mol%, and wherein, in the silica glass composition, the sum of Li2O + Na2O is from 0 to 1.75 mol%.

42. A glass sheet comprising:a silica glass composition comprising (in mol%): greater than or equal to 61.0 SiO2; from 0 to 0.65 F; from 0.01 to 1.0 Eu2O3; and greater than or equal to 0.01 of a sum of CeO2 and Ce2O3; wherein, in the silica glass composition, R2O + (BeO + CaO + SrO + BaO + ZnO) – Al2O3– B2O3is within a range of from -50 mol% to 10 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.

43. A glass sheet comprising:a silica glass composition comprising (in mol%): from 61.0 to 95.0 SiO2; from 0 to 12.5 Na2O; from 0 to 0.65 F;Attorney Docket No. SP24-152PCT from 0.005 to 0.17 of a sum of Eu2O3and EuO; from 0 to 0.3 Ti2O; and from 0 to 4.0 ZrO2; wherein, in the silica glass composition, R2O + (BeO + MgO + CaO + SrO + BaO ) – Al2O3 – B2O3 – (MgO / 4) is within a range of from -50 mol% to 12 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.

44. A glass sheet comprising:a silica glass composition comprising (in mol%): greater than or equal to 61.0 SiO2; from 0.01 to 1.0 Eu2O3; greater than or equal 0.01 of a sum of Ce2O3 and CeO2; and from 0 to 0.05 Tb2O3; wherein, in the silica glass composition, R2O + (BeO + CaO + SrO + BaO + ZnO) – Al2O3 – B2O3 is within a range of from -50 mol% to 10 mol%, where R2O is the sum of all alkali oxides of the silica glass composition.

45. A glass sheet comprising:a silica glass composition comprising (in mol%): from 60.0 to 69.9 SiO2; from 0.1 to 22.0 Al2O3; from 0 to 25.0 B2O3; from 0.04 to 0.35 of a sum of Ce2O3 and CeO2; from 0 to 0.05 Fe2O3; from 0 to 0.25 TiO2; from 0 to 1.0 PbO; and from 0 to 0.1 As2O3; wherein, in the silica glass composition, Li2O + Na2O is within a range of from 0 mol% to 1.75 mol%, wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3is within a range of from -40 mol% to 0.85 mol%, and wherein, in the silica glass composition, Sb2O3 +Yb2O3 + Y2O3 is within a range of from 0 to 0.4 mol%.Attorney Docket No. SP24-152PCT46. A glass sheet comprising:a silica glass composition comprising (in mol%): from 60.0 to 75.0 SiO2; from 0.10 to 25.0 Al2O3; from 0 to 3.0 B2O3; from 0 to 1.0 BaO; from 0.04 to 0.35 of a sum of Ce2O3and CeO2; from 0 to 0.25 TiO2; and from 0 to 1 PbO; wherein, in the silica glass composition, Li2O + Na2O is within a range of from 0 to 1.75 mol%, and wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3 is within a range of from -40 mol% to 2.2 mol%, and wherein, in the silica glass composition, La2O3+ Y2O3+ Pr2O3+ Nd2O3+ Tm2O3+ Er2O3 + Ho2O3 + Lu2O3 is within a range of from 0 to 0.5 mol%.

47. A glass sheet comprising:a silica glass composition comprising (in mol%): from 60.0 to 75.0 SiO2; from 0.1 to 25.0 Al2O3; from 0 to 9.35 B2O3; and from 0 to 1.0 BaO; from 0.04 to 0.35 of a sum of Ce2O3 and CeO2; from 0 to 1.0 PbO; and from 0 to 0.25 TiO2; wherein, in the silica glass composition, Li2O + Na2O is within a range of from 0 to 1.75 mol%, wherein, in the silica glass composition, (BeO + MgO + CaO + SrO + BaO) – Al2O3 is within a range of from -40 mol% to 3.0 mol%, and wherein, in the silica glass composition, La2O3+ Y2O3+ Pr2O3+ Nd2O3+ Gd2O3+ Tm2O3+ Er2O3+ Ho2O3+ Lu2O3is within a range of from 0 to 0.1 mol%.

48. A glass sheet comprising:a silica glass composition comprising (in mol%):Attorney Docket No. SP24-152PCT from 61.0 to 99.95 SiO2; from 0 to 12.5 NaO2; from 0 to 0.65 F; from 0.005 to 0.17 of a sum of Eu2O3and EuO; from 0 to 0.05 Fe2O3; from 0 to 0.3 TiO2; and from 0 to 4.0 ZrO2; wherein, in the silica glass composition, Al2O3 / (Eu2O3 + Ce2O3 + (CeO2 / 2) is greater than or equal to 3.5 mol%.

49. A solar panel comprising:one or more photovoltaic cells; and the glass sheet of any one of claims 1-48 positioned relative to the one or more photovoltaic cells such that electromagnetic radiation transmits through the glass sheet and impinges upon the one or more photovoltaic cells.

50. The solar panel of claim 49, whereinthe glass sheet comprises a first primary surface, a second primary surface, and a thickness between the first primary surface and the second primary surface, and the thickness of the glass sheet is less than 1.0 mm.

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