Dye-loaded zeolite composites

Abstract

The invention relates to the technical field of optical materials and devices. In particular, the present invention relates to dye-loaded composites. The invention also relates to a zeolite-polymer hybrid material and a luminescent concentrator. The invention also relates to a method for preparing the dye-loaded composite material, and to the use of the dye-loaded composite material, the zeolite-polymer hybrid material and the luminescent concentrator.

Description

[0001] The present invention relates to the technical field of optical materials and devices. In particular, the present invention relates to dye-loaded composites. The present invention further relates to zeolite-polymer hybrid materials and luminescent concentrators. The present invention further relates to a method for preparing dye-loaded composites, as well as the use of dye-loaded composites, zeolite-polymer hybrid materials and luminescent concentrators.

[0002] Zeolites are porous aluminosilicate minerals commonly used as commercial adsorbents and catalysts. Zeolites are characterized by a three-dimensional framework of tetrahedrally linked aluminum oxide and silicon dioxide units, with high surface area and well-defined pore structure. These features make zeolites very effective in selective adsorption and ion exchange processes.

[0003] Dye-loaded zeolite composites combine the porous structure of zeolites and the optoelectronic properties of organic dyes. Through methods such as encapsulation or adsorption, dye molecules are integrated into the zeolite framework. This results in improved stability, tunable photophysical properties and increased adsorption capacity. These composites have potential applications in various fields, including photovoltaics, sensors and catalysis.

[0004] Patent EP1873202B1 (CLARIANT FINANCE, UNIV BERN, OPTICAL ADDITIVES, 29 June 2006) discloses a transparent zeolite-polymer hybrid material with tunable properties. The material comprises dye-loaded zeolite composites dispersed in a polymer matrix. This material is known for its transparency and tunable properties, making it versatile for various applications, such as for lenses, eyeglasses, polarizers, monitors or window glass.

[0005] In EP3434748B1 (MERZ BENTELI AG, 26 July 2017), a method for preparing L-type zeolite materials containing guest molecules is disclosed. The innovation of this method lies in the use of cyclic siloxanes as transport agents for guest molecules. This enables the addition of guest molecules to the channels of L-type zeolite crystals.

[0006] Luminescent solar concentrators (LSCs) or luminescent concentrators are optical devices designed to improve the efficiency of light energy collection systems. LSCs comprise a transparent substrate embedded with a luminescent material, which can absorb sunlight and re-emit it at a longer wavelength. This re-emitted light is directed to the edges of the substrate, where it is concentrated onto photovoltaic cells for conversion into electrical energy. The ability of LSCs to collect diffuse sunlight makes them particularly useful in low-light conditions, thus broadening the range of environments in which light energy can be effectively collected.

[0007] LSCs comprising dye-loaded zeolite composites are described in the prior art. Patent EP 2291484 B1 (CALZAFERRI GION, KUNZMANN ANDREAS, UNIV ZUERICH, 31 March 2009) focuses on the integration of luminescent dyes into zeolite structures to make devices capable of efficient light harvesting or light spreading. Patent EP 2791274 B1 (CALZAFERRI GION, KUNZMANN ANDREAS, UNIV ZUERICH, 10 December 2012) discloses a composite material that binds dye molecules to the zeolite structure. The invention focuses on local J-coupling between dye molecules within the zeolite channels, enhancing the luminescent properties of the material.

[0008] While the encapsulation of guest molecules such as dyes in zeolites can improve the stability of the guest molecules against photo-degradation, thermal degradation, oxidation and reduction, as well as against acids and bases, it has been found that the long-term stability of guest molecules, especially dye molecules, is insufficient for many applications in the prior art systems and methods.

[0009] Especially in applications involving strong and continuous electromagnetic wave irradiation, such as the use of these systems as LSCs, it is often found that despite the encapsulation of the dyes, they still decompose under the influence of photo-degradation. Especially acid-sensitive guest molecules tend to decompose over time.

[0010] It is therefore an object of the present invention to overcome at least some, if not all, of the disadvantages of the prior art methods. In particular, it is an object of the present invention to provide dye-loaded zeolite composites with enhanced long-term stability. The long-term stability should be maintained, especially against the effects of photochemistry, heat, oxidation, reduction, as well as against acids and bases, especially against acids.

[0011] The object is solved by a dye-loaded zeolite composite, a zeolite-polymer hybrid material, a luminescent light harvester, a method for preparing a dye-loaded composite material, and the use of a dye-loaded composite material, a zeolite-polymer hybrid material and a luminescent light harvester according to the independent claims. Advantageous embodiments and further improvements are the subject of the dependent claims.

[0012] A first aspect of the present invention relates to a dye-loaded zeolite composite. The material comprises a plurality of zeolite crystals, the zeolite crystals comprising pores having a pore size. It further comprises a plurality of dye molecules, especially luminescent dye molecules, in the pores. The spatial extent of at least two mutually perpendicular dimensions of each dye molecule is smaller than the pore size.

[0013] The material is characterized in that the plurality of zeolite crystals comprises at least 5 moles of SiO2per mole of Al2O3, preferably at least 10 moles of SiO2per mole of Al2O3, more preferably at least 50 moles of SiO2per mole of Al2O3, even more preferably at least 100 moles of SiO2per mole of Al2O3, even more preferably at least 200 moles of SiO2per mole of Al2O3, most preferably at least 400 moles of SiO2per mole of Al2O3. Alternatively, the material is characterized in that the zeolite crystals are aluminophosphate zeolite crystals.

[0014] Zeolites are aluminosilicate compounds that form a framework of tetrahedra of silicon cations (Si 4+ ) and aluminum cations (Al 3+ ) surrounded by oxygen anions (O 2- ). The oxygen atoms form bonds between the Si-O and Al-O tetrahedra. Different arrangements of these shared-oxygen tetrahedra result in different geometric forms of the crystalline structure containing polyhedral pores. Windows are rings formed of tetrahedral units that define a face of a polyhedral pore. Cages are polyhedral pores with narrow windows that do not allow the passage of molecules larger than water. Cavities are polyhedral pores that have at least one face defined by a ring large enough to allow the penetration of guest species larger than water, but not infinitely extended. Channels are pores that are infinitely extended in one dimension and have a width sufficient to allow the diffusion of guest molecules larger than water along their length. VILLARROEL-ROCHA J. et al. (Critical Overview of Textural Characterization of Zeolites by Gas Adsorption. Cham: Springer, 2020, Vol. 18) provides a comprehensive definition of the pores in zeolites.

[0015] In the context of the present invention, the pore diameter is defined by the free diameter, which refers to the diameter of the largest sphere that can pass through the pore. VILLARROEL-ROCHA J. et al. (Critical Overview of Textural Characterization of Zeolites by Gas Adsorption. Cham: Springer, 2020, Vol. 184) describes methods for determining the pore diameter for different types of pore geometry.

[0016] All pores deviating from the nominal pore diameter by at most 30%, preferably at most 20%, most preferably at most 10% are considered to belong to the nominal pore diameter.

[0017] If the zeolite type comprises more than one pore type with different pore diameters, the pore diameter corresponds to the largest pore diameter of the zeolite type.

[0018] The plurality of dye molecules according to the present application can comprise one type of molecule or a combination of different types of molecules.

[0019] The dye molecules are selected such that a Förster resonance energy transfer between individual molecules can occur.

[0020] Suitable molecules for the dye-loaded zeolite composite according to the present application have been described in EP 1873202 B1 (CLARIANT FINANCE, UNIV BERN, OPTICAL ADDITIVES, 29 June 2006), EP 2291484 B1 (CALZAFERRI GION, KUNZMANN ANDREAS, UNIV ZUERICH, 31 March 2009) and EP 2791274 B1 (CALZAFERRI GION, KUNZMANN ANDREAS, UNIV ZUERICH, 10 December 2012).

[0021] The plurality of dye molecules of the dye-loaded zeolite composite according to the present application is small enough to fit into the pores of the zeolite crystal. They are adsorbed at the pore surface.

[0022] The SiO2 / Al2O3 molar ratio in the zeolite can be adjusted by selective solid-state synthesis or by post-synthetic modification of the zeolite framework, for example by dealumination using inorganic acids such as HC1 or HNO3, or by steam treatment. In the prior art, essentially aluminium-free zeolites are known (Wragg D. S. et al., Pure Silica Zeolite-type Frameworks: A Structural Analysis. Chem. Mater. 2008, No. 20, pages 1561 to 1570). For example, a SiO2 / Al2O3 molar ratio of 10: 1 corresponds to a Si / Al molar ratio of 5: 1, since there are two Al atoms in Al2O3.

[0023] Preferably, the zeolite crystal is essentially free of aluminium.

[0024] In the context of the present invention, aluminophosphate zeolite crystals are aluminophosphate materials with properties similar to zeolites. They are also microporous crystalline materials with a similar framework structure as conventional zeolites. Such aluminophosphate materials are disclosed and further described in e.g. RUNGROJCHAIPON P. et al. (Microporous Mesoporous Mater. 2008, Vol. 109, No. 1-3, pages 478-484).

[0025] It has surprisingly been found that the dye molecules comprised in the dye-loaded zeolite composite according to the present invention exhibit a long-lasting stability, in particular against photochemical, thermal, oxidative, reductive as well as acidic and basic influences. In particular with zeolites having a particularly high molar ratio of SiO2 / Al2O3, it was found that the lifetime of the dye as guest molecule is particularly good.

[0026] Without being bound to theory, the long-term stability of the added dye molecules is explained as follows. The isomorphous exchange of Si 3+ with Al 4+ brings a positive charge into the zeolite framework, thus removing Brönsted acid sites. As a consequence, the protons balancing the excess of negative charge caused by Al 3+ are also removed. Thus, a low proportion of aluminum relative to silicon in the zeolite crystals leads to an overall low concentration of Brönsted acids.

[0027] It is therefore assumed that a high concentration of Brönsted acids in zeolite crystals having a low molar ratio of SiO2 / Al2O3 favors various decomposition reactions of the dye. Thus, in zeolites having a high molar ratio of SiO2 / Al2O3, the more pH-neutral environment leads to less Brönsted acid-promoted such decomposition reactions.

[0028] In contrast to zeolites, aluminophosphate zeolites completely lack Brönsted acid sites. Based on the same reasoning as described above, it can thus be said that due to the lack of Brönsted acid sites, aluminophosphate zeolites also lead to less decomposition reactions of the dye guest molecules.

[0029] This surprising high stability of the dye molecules in the dye-loaded zeolite composite is particularly advantageous for applications in which the dye molecules are exposed to extreme conditions for a long time. Such applications include LSCs in which the dye molecules are exposed to direct sunlight for decades.

[0030] In a preferred embodiment of the first aspect of the present invention, the type of zeolite crystals is L-zeolite, Y-zeolite, mordenite, ferrierite, pentasil, BETA, AlPO-5, AlPO-15, AlPO-36 or a combination thereof.

[0031] L-type zeolites are characterized by their one-dimensional, straight channels. Y-type zeolites are octahedral zeolites with a three-dimensional pore system. Morder zeolites are zeolites with channels of varying sizes. Pentasil is a family of zeolites that includes ZSM-5, which has a three-dimensional pore structure. BETA-type zeolites also have a three-dimensional pore structure.

[0032] AlPO-5 (aluminum phosphate-5) is a molecular sieve with one-dimensional, non-communicating channels. AlPO-15 is characterized by its three-dimensional porous structure. AlPO-36 contains large cages connected by 8-ring windows.

[0033] It has been found that these types of zeolites and aluminophosphate zeolites achieve good stability of the added dye molecules.

[0034] In another preferred embodiment of the first aspect of the invention, the pore size is at least 0.5 nm, preferably at least 0.7 nm, and more preferably at least 0.9 nm.

[0035] The aperture and acceptable aperture size distribution have been defined above.

[0036] It has been shown that larger dye molecules are more suitable for the application of dye-loaded zeolite composites, where the long-term stability of the dye molecules is an advantage.

[0037] Furthermore, it has been found that the absorption wavelength of dye molecules is generally proportional to the size of the molecules. For applications requiring smaller absorption wavelengths, smaller molecules, and therefore zeolites with smaller pore sizes, are the obvious choice.

[0038] In another preferred embodiment of the first aspect of the present invention, the dye molecule is selected from: perylene dyes, terylene dyes, cyanine dyes, oxazine dyes, BODIPY dyes, stilbene dyes, xanthannaphthalene dyes, POPOP, dimethyl POPOP, biphenyls, terphenyls, tetraphenyls, tetraphenylbenzenes, tribenzodioxazines, acridines, stilbene, azobenzenes, oxazolylbenzenes, styrylbenzenes, fluorenones, isoviolanthrones, thioindole compounds, as well as spiropyrans, naphthopyrans, carotenoids, carotenes, lutein, xanthophyll, pyronines, oxazines, thiocyanates, resorufine, methyl viologen, carbocyanines, zethrene, rhodamine dyes, rhodamine 800, tetramethylrhodamine, BTA-TPA, ESi5a–ESi5d, tb-DXP, Ampliite ADHP, Ampliite IR, LysoBrite TMRed DND-99, Alexa Fluor dyes, KFL-1, KFL-3, KFL-11, KFL-12, KFL-13, TM-BDP, p-terphenyl, fluorescein, thodamine dyes, cyanine dyes, pyrene dyes, Janelia dyes, SiR-Hoechst dyes, Phiton dyes, hostasolred, oxonines, PDI dyes, dm-XP, Pigment Red 149, DMP, Pyronin, halogenated ( Resorufin (Res), hydroxy-TEMPO, biphenyl, DPH, MBOXE, 6-(((4-(4,4-difluoro-5-(2-thienyl)-4-bora-3a,4a-diaza-s-indarsen-3-yl)phenoxy)acetyl)amino)hexanoic acid succinimide, 4,5-difluoro-5,7-diphenyl-4-bora-3a,4a-diaza-s-indarsen-3-propionyl ethylenediamine hydrochloride, pyrrolidine G, fluorenone and any combination thereof.

[0039] BTA-TPA has been described by LUO Q. et al. (Deep-red fluorescence from isolated dimers: ahighly bright excimer and imaging in vivo. Chem. Sci. 2020, Vol. 11, page 6020).

[0040] ESi5a–ESi5d has been described by LI J. et al. (Stable, Bright, and Long-Fluorescence-Lifetime Dyes for Deep-Near-Infrared Bioimaging. J. Am. Chem. Soc. 2022, Vol.144, No. 31, pages 14351 to 14362).

[0041] Preferably, the (multiple) xaton dyes are or contain 2-((6-hydroxy-2,3-dihydro-1H-xaton-4-yl)methylene)malonitrile.

[0042] BODIPY (boron-dipyrrolemethylene) dye is a type of fluorescent dye. The core structure of BODIPY (CAS 138026-71-8) consists of boron atoms coordinated with two dipyrrolemethylene ligands, forming a planar and highly conjugated system.

[0043] POPOP (1,4-bis(5-phenyloxazol-2-yl)benzene; CAS 1806-34-4) is an organic scintillator dye.

[0044] Dimethyl POPOP is known as 4-methyl-2-[4-(4-methyl-5-phenyl-1,3-oxazol-2-yl)phenyl]-5-phenyl-1,3-oxazol (CAS 3073-87-8, maximum absorption wavelength (cyclohexane): 362 nm; maximum emission wavelength (cyclohexane): 419 nm).

[0045] tb-DXP has been described by CAO P. et al. (Supramolecular Organization of Dye Molecules in Zeolite L Channels: Synthesis, Properties, and Composite Materials. Chemistry. 2016, Vol. 22, No. 12, pages 4046 to 4060).

[0046] Oxazine 1 is a molecule with CAS number 24796-94-9. Oxazine 1 is a derivative of an oxazine with a maximum absorption wavelength of 648 nm (L-type zeolite) and a maximum emission wavelength of 668 nm (L-type zeolite) (https: / / www.aatbio.com / resources / assaywise / 2015-4-2 / peroxidase-detection).

[0047] Amplite ADHP, LysoBrite TM Red DND-99 is a molecule according to Formula 1.

[0048]

[0049] Formula 1

[0050] Preferably, the plurality of dye molecules comprise any of the following compositions:

[0051] - Dimethyl POPOP, Amplite ADHP, and Amplite IR;

[0052] - Dimethyl POPOP, Amplite ADHP, Amplite IR and BODIPY 576 / 589;

[0053] - Dimethyl POPOP, Amplite ADHP, Amplite IR, and Alexa Fluor 546;

[0054] - KFL-11, KFL-1 and optional KFL-13;

[0055] - KFL-11, KFL-1, TM-BDP, optional KFL-12 and optional KFL-13;

[0056] - Dimethyl POPOP, KFL-11, KFL-1, KFL-12, KFL-3;

[0057] - TPB and dimethylPOPOP;

[0058] - For terphenyl, dimethylpOPOP and perylene,

[0059] - p-Triphenyl, dimethylPOPOP, perylene, BODIPY 500 / 510, BODIPY TMR, BODIPY 581 / 591, Bodi Fluor 576 / 589 NHS ester and BODIPY 630 / 650.

[0060] The CAS number for BODIPY 576 / 589 is 150173-78-7, and the CAS number for BODIPY 500 / 510 is 144672-74-2.

[0061] KFL-1, KFL-3, KFL-11, KFL-12, KFL-13 and TM-BDP have been described by UMEZAWA K. et al. (Bright, Color-Tunable Fluorescent Dyes in the Vis / NIR Region: Establishment of New “Tailor-Made” Multicolor Fluorophores Based on Borondipyrromethene. Chem.Eur. J. 2009, Vol. 15, No. 5, pages 1096 to 1106).

[0062] dm-XP is 2,9-bis(2,6-dimethylphenyl)anthra[2,1,9-def:6,5,10-d'e'f']-diisoquinoline-1,3,8,10(2H, 9H)tetraone.

[0063] Pigment Red 149 is 2,9-bis(3,5-dimethylphenyl)anthra[2,1,9-def:6,5,10-'e'f']diisoquinoline-1,3,8,10-(2H,-9H)-tetraone.

[0064] Hostasol Red is 14H-anthra[2,1,9-mna]thioxanthox-14-one (Hostasol Red).

[0065] DMP is 1,4-bis(4-methyl-5-phenyloxazol-2-yl)benzene.

[0066] DPH is 1,6-diphenylhextriene.

[0067] MBOXE is 1,2-bis-<5-methyl-benzoxazol-2-yl>-ethylene.

[0068] The list of molecules and molecular categories mentioned includes both core molecules and their derivatives. In the context of this invention, derivatives of the core molecule are molecules in which up to six, preferably up to four, and most preferably up to two functional groups and / or hydrogen atoms are each replaced by different functional groups or hydrogen atoms.

[0069] Preferably, the dye-loaded zeolite composite material according to the present invention comprises the following zeolite-dye combination:

[0070] - L-type zeolite and perylene;

[0071] - L-type zeolite and trinaphthalene-containing benzoylene;

[0072] - L-type zeolite and popop;

[0073] - L-type zeolite and hostasol red

[0074] - Magnesium alkali zeolite and p-terphenyl;

[0075] - Mordant zeolite and Popop;

[0076] - Y-type zeolite and compounds 1-5 from DAI J. et al. (Molecular Conformation Engineering To Achieve Longer and Brighter Deep Red / Near-Infrared Emission in Crystalline State, J.Phys. Chem. lett. 2022, Vol. 13, No. 21, pages 4754 to 4761);

[0077] - pentasil and BODIPY;

[0078] - pentasil and cyanine dyes;

[0079] - BETA and zeolite;

[0080] - BETA and BODIPY;

[0081] - Mordant zeolite and hostasol red; or

[0082] - Any combination of these zeolite-dye combinations.

[0083] In a preferred embodiment of the first aspect of the invention, more than 90%, preferably more than 95%, and most preferably more than 99% of the pore openings on the outer surface of the zeolite crystal are each occupied by dye molecules, wherein the dye molecules are partially surrounded by the pores and partially protrude from the openings, and wherein the dye molecules are connected to the outer surface via chemical bonds, preferably silane-hydroxyl bonds.

[0084] This seals the pore openings, preventing the penetration of unwanted molecules such as water and oxygen. Therefore, this results in a particularly stable zeolite composite material for loading dyes.

[0085] A second aspect of the invention relates to a zeolite-polymer hybrid material. The material comprises a transparent polymer or a transparent polymer composition. It also comprises a dye-loaded zeolite composite material of the first aspect of the invention. The dye-loaded zeolite composite material is embedded as one layer, or two or more spaced-apart layers, into the transparent polymer or transparent polymer composition. The zeolite-polymer hybrid material optionally comprises a varnish and / or coating for application to the transparent polymer or transparent polymer composition or glass.

[0086] In the context of this invention, the terms "transparent polymer" and "transparent polymer composition" refer to polymeric materials that exhibit at least 90% light transmittance in the visible spectral range of 400 nm to 700 nm according to ASTM D1003-21 (June 7, 2021). The material should also exhibit a haze value of less than 5% according to ASTM D1003-21 (June 7, 2021) to ensure minimal light scattering.

[0087] The preparation of zeolite-polymer hybrid materials according to the present invention, suitable polymers, properties and uses are described in EP1873202B1 (CLARIANT FINANCE, UNIV BERN, OPTICAL ADDITIVES, June 29, 2006).

[0088] The amount of zeolite crystals dispersed in the transparent polymer or transparent polymer composition relative to the total volume of the hybrid material is preferably from 0.005% volume / volume to 40% volume / volume, for example from 0.5% volume / volume to 25% volume / volume.

[0089] The dye-loaded composite material according to the present invention is preferably a dye-loaded composite material layer.

[0090] The use of the dye-loaded zeolite composite material according to the first aspect of the invention in the zeolite-polymer hybrid material according to the second aspect of the invention results in the added dye molecules having a longer lifetime.

[0091] In a preferred embodiment of the second aspect of the invention, the transparent polymer or transparent polymer composition comprises polyolefin, polysiloxane, polyacrylate, polymethacrylate, polyethylene, polyester, polycarbonate, polyurethane, or a combination thereof.

[0092] The preparation of one or more polymers of a polymer composition is described in EP1873202B1 (CLARIANT FINANCE, UNIV BERN, OPTICAL ADDITIVES, 29 June 2006).

[0093] A polymer made from diethylene glycol dielyl carbonate, hereinafter referred to as CR-39, is particularly preferred. CR-39 can be obtained by polymerizing the liquid monomer diethylene glycol dielyl carbonate with 3% to 6% by weight of benzoyl peroxide as an initiator. The two allyl groups achieve cross-linking polymerization, resulting in a hard, insoluble, and transparent material.

[0094] In a preferred embodiment of the second aspect of the invention, the zeolite-polymer hybrid material is in fibrous form.

[0095] A third aspect of the invention relates to a light-emitting concentrator comprising a zeolite-polymer hybrid material according to the second aspect of the invention. It further comprises a substrate and a top sheet on the zeolite-polymer hybrid material, wherein the substrate and top sheet are transparent sheets suitable for total internal reflection and are made of glass, plastic, or a combination thereof. The light-emitting concentrator optionally includes a varnish and / or coating for application to the substrate and / or top sheet.

[0096] Preferably, the light-emitting concentrator of the present invention is a light-emitting solar concentrator.

[0097] The structure and working principle of the light-emitting concentrator according to the invention, which can be produced using the zeolite-polymer hybrid material according to the invention, are described in EP2291484B1 (CALZAFERRI GION, KUNZMANN ANDREAS, UNIV ZUERICH, March 31, 2009).

[0098] The dye-loaded zeolite composite material of the first aspect of the present invention increases the lifespan of the light-emitting concentrator.

[0099] A fourth aspect of the invention relates to a light-emitting concentrator for focusing light to a point, comprising a zeolite-polymer hybrid material of the second aspect of the invention or a light-emitting concentrator of the third aspect of the invention. It further comprises at least one fiber optic light-emitting concentrator optically coupled to at least one edge of the zeolite-polymer hybrid material or the light-emitting concentrator.

[0100] In the context of this invention, objects can be optically coupled to each other when they are in physical contact with each other or when there is a gap filled with gas or a vacuum between two devices.

[0101] In the context of this invention, the phrase "concentrating light to a point" refers to the process of directing ray beams so that they converge at a specific geometric location in space. This location, referred to as a "point," is defined as an area with a diameter not exceeding 5 mm, preferably not exceeding 2 mm, more preferably not exceeding 1 mm, and most preferably not exceeding 0.5 mm. Therefore, the term "point" should not be interpreted as an infinitesimally small geometric location, but rather as a finite region.

[0102] A “fiber optic light-emitting concentrator” comprises an optical fiber core into which a light-emitting material is injected to absorb incident light and re-emit it at different wavelengths. The emitted light is guided through the optical fiber in one dimension by internal reflection and concentrated at one or both ends, where it can be coupled to, for example, a photovoltaic cell for energy conversion. The light can also be coupled to optical fibers for various applications. In the context of this invention, the light-emitting material is preferably a dye-loaded zeolite composite material, as described in the first aspect of the invention. When the light source is a conventional LSC, the optical fiber is connected to the LSC via optical contacts (on the front, back, or at least one edge). The emission wavelength of the LSC should be equal to or shorter than the absorption wavelength of the fiber LSC.

[0103] The seventh aspect of the present invention relates to a photovoltaic device comprising a light-emitting concentrator according to the fifth aspect of the present invention, and a light energy converter optically coupled to the light-emitting concentrator.

[0104] The light-emitting concentrator includes at least two different types of dye molecules, wherein the at least two different types of dye molecules convert the wavelength of incident light from 500 nm to 600 nm to a wavelength greater than 600 nm through a Foster resonance energy transfer cascade.

[0105] A solar energy converter converts light energy into another form of energy, preferably electrical energy. Preferably, the solar energy converter is a photovoltaic cell.

[0106] The light with a wavelength greater than 600 nm generated by this process can be converted into electrical energy by photovoltaic cells, or it can be emitted as light energy to (one or more) photosynthetic plants.

[0107] A fifth aspect of the present invention relates to a method for preparing a composite material for loading dyes according to the first aspect of the present invention. The method includes the step of preparing a mixture comprising a plurality of zeolite crystals having pores of a specific size. The plurality of zeolite crystals comprises at least 100 moles of SiO2 per mole of Al2O3, preferably at least 200 moles of SiO2 per mole of Al2O3, more preferably at least 400 moles of SiO2 per mole of Al2O3. Alternatively, the zeolite crystals are aluminophosphate zeolite crystals. The mixture further comprises a plurality of dye molecules, wherein at least two mutually perpendicular dimensions of each dye molecule have a spatial extent smaller than the pore size. The mixture further comprises a solvent, wherein the solvent is or comprises cyclic siloxanes, perfluorinated solvents, sterically hindered aromatic solvents, crown ethers, triglycerides, 9-ethyl-9-heptyloctadecane, 2,2,4,15,17,17-hexamethyl-7,12-bis(3,5,5-trimethylhexyl)octadecane, 3-heptadecane, 5-decyl-5-heptyl-2,2-dimethyl, 3-heptadecaneol, 5-decyl-5-heptyl-2,2-dimethyl, 2,2,4,10,12,12-hexamethyl-7-(3,5,5-trimethylhexyl)tridecane, 8-hexyl-8-pentylhexadecane, esters, linoleic acid, stearic acid, trans-oleic acid, or combinations thereof. The mixture is heated to at least 100°C, preferably at least 120°C, more preferably at least 140°C, to obtain a dye-loaded composite material.

[0108] Cyclic siloxanes suitable for the method according to the invention are described in EP3434748B1 (MERZ BENTELI AG, July 26, 2017). Further preferred cyclic siloxanes are decamethylcyclopentane and octamethylcyclotetrasiloxane.

[0109] Preferably, the perfluorinated solvent is perfluorohexane, perfluoronaphthane, perfluorotributylamine, or a combination thereof.

[0110] In a preferred embodiment of the fifth aspect of the invention, the method further includes the step of removing water from the solvent before adding the solvent to the mixture to a maximum water content of 0.1% by weight, preferably 0.01% by weight, and most preferably 0.001% by weight. Alternatively or additionally, the method further includes the step of drying a plurality of zeolite crystals at a temperature of at least 110°C, preferably at least 130°C, and most preferably at least 150°C, for at least 2 hours, preferably at least 5 hours, and most preferably at least 8 hours before adding the zeolite crystals to the mixture.

[0111] The water content of a solvent was quantitatively determined using the Karl Fischer titration method according to ASTM E1064-16 (August 1, 2023).

[0112] The sixth aspect of the present invention relates to the use of the dye-loaded composite material of the first aspect of the present invention, the zeolite-polymer hybrid material of the second aspect of the present invention, or the light-emitting concentrator of the third or fourth aspect of the present invention in photovoltaic devices.

[0113] In a preferred embodiment of the sixth aspect of the invention, the photovoltaic device is integrated into window glass, greenhouse roof, panel covering photosynthetic plants, or any combination thereof.

[0114] Figure 1 A and Figure 1 B schematically illustrates a preferred embodiment of the first aspect of the invention. Dye molecules (3) are fixed at the openings of pores (4) in zeolite crystals (2) that are part of a zeolite composite material (1) loaded with dye.

Claims

1. A dye-loaded zeolite composite material (1), comprising: - Multiple zeolite crystals (2), which contain pores (4) with pore sizes, and - Multiple dye molecules (3), particularly luminescent dye molecules (3), in the pore (4), wherein the spatial extent of at least two mutually perpendicular dimensions of each dye molecule (3) is smaller than the pore size; Its features -The plurality of zeolite crystals (2) contain at least 5 moles of SiO2 per mole of Al2O3, preferably at least 10 moles of SiO2 per mole of Al2O3, more preferably at least 50 moles of SiO2 per mole of Al2O3, even more preferably at least 100 moles of SiO2 per mole of Al2O3, even more preferably at least 200 moles of SiO2 per mole of Al2O3, and most preferably at least 400 moles of SiO2 per mole of Al2O3; or - The zeolite crystal (2) is an aluminophosphate zeolite crystal.

2. The dye-loaded zeolite composite material (1) according to claim 1, wherein the zeolite crystals (2) are of the type of L-type zeolite, Y-type zeolite, mordenite, magnesium alkali zeolite, pentasil, BETA, AlPO-5, AlPO-15, AlPO-36 or a combination thereof.

3. The dye-loaded zeolite composite material (1) according to any one of the preceding claims, wherein the pore size is at least 0.5 nm, preferably at least 0.7 nm, more preferably at least 0.9 nm.

4. The zeolite composite material (1) with dye loaded according to any one of the preceding claims, wherein the dye molecule (3) is selected from: perylene dyes, terylene dyes. Dyes, including cyanine dyes, oxazine dyes, BODIPY dyes, stilbene dyes, xanthannaphthalene dyes, POPOP, dimethyl POPOP, biphenyls, terphenyls, tetraphenyls, tetraphenylbenzenes, tribenzodioxazines, acridines, stilbene, azobenzenes, oxazolylbenzenes, styrylbenzenes, fluorenones, isoviolanthrones, thioindole compounds, as well as spiropyrans, naphthopyrans, carotenoids, carotenes, lutein, xanthophyll, pyronines, oxazines, thiocyanates, resorufine, methyl viologen, carbocyanines, zethrene, rhodamine dyes, rhodamine 800, tetramethylrhodamine, BTA-TPA, ESi5a–ESi5d, tb-DXP, Ampliite ADHP, Ampliite IR, LysoBrite. TM Red DND-99, Alexa Fluor dyes, KFL-1, KFL-3, KFL-11, KFL-12, KFL-13, TM-BDP, p-terphenyl, fluorescein, thodamine dyes, cyanine dyes, pyrene dyes, Janelia dyes, SiR-Hoechst dyes, Phiton dyes, hostasol red, oxonines, PDI dyes, dm-XP, Pigment Red 149, DMP, Pyronine, Resorufin (Res), hydroxy-TEMPO, biphenyl, DPH, MBOXE, 6-(((4-(4,4-difluoro-5-(2-thienyl)-4-boraza-3a,4a-diaza-s-indarsen-3-yl)phenoxy)acetyl)amino)hexanoic acid succinimide, 4,5-difluoro-5,7-diphenyl-4-boraza-3a,4a-diaza-s-indarsen-3-propionyl ethylenediamine hydrochloride, Pyronine G, fluorenone and any combination thereof.

5. The dye-loaded zeolite composite material (1) according to any one of the preceding claims, wherein more than 90%, preferably more than 95%, and most preferably more than 99% of the pore openings on the outer surface of the zeolite crystal (2) are each occupied by a dye molecule (3), wherein the dye molecule (3) is partially surrounded by the pore (4) and partially protrudes from the opening, and wherein the dye molecule (3) is connected to the outer surface via a chemical bond, preferably a silane-hydroxy bond.

6. A zeolite-polymer hybrid material comprising: -Transparent polymers or transparent polymer compositions, -The zeolite composite material (1) loaded with dye according to any one of the preceding claims, which is embedded as one layer, or two or more spaced-apart layers, into the transparent polymer or transparent polymer composition, and -Optional varnishes and / or coatings for application to the transparent polymer or transparent polymer composition or glass.

7. The zeolite-polymer hybrid material of claim 6, wherein the transparent polymer or transparent polymer composition comprises polyolefin, polysiloxane, polyacrylate, polymethacrylate, polyethylene, polyester, polycarbonate, polyurethane or a combination thereof.

8. The zeolite-polymer hybrid material according to claims 6 to 7, wherein the zeolite-polymer hybrid material is in the form of fibers.

9. A light-emitting concentrator, comprising: -The zeolite-polymer hybrid material according to claims 6 to 8 - A substrate and a top sheet on the zeolite-polymer hybrid material, wherein the substrate and the top sheet are transparent sheets suitable for total internal reflection and are made of glass, plastic, or a combination thereof, and - Optional varnish and / or coating to be applied to the substrate and / or the top sheet.

10. A light-emitting concentrator for focusing light to a point, comprising: -The zeolite-polymer hybrid material according to claims 6 to 8, or the light-emitting concentrator according to claim 9, - At least one fiber optic light-emitting concentrator, which is optically coupled to at least one edge of the zeolite-polymer hybrid material or the light-emitting concentrator.

11. A photovoltaic device, comprising: -The light-emitting concentrator according to claim 9 or 10, and - A light energy converter optically coupled to the light-emitting concentrator; The light-emitting concentrator comprises at least two different types of dye molecules, wherein the at least two different types of dye molecules convert the wavelength of incident light from 500 nm to 600 nm into a wavelength greater than 600 nm through a Foster resonance energy transfer cascade.

12. A method for preparing a composite material (1) with a dye-loaded material according to any one of claims 1 to 5, the method comprising the following steps: -Preparing a mixture comprising: - Contains multiple zeolite crystals with pores of varying sizes, wherein -The plurality of zeolite crystals contain at least 100 moles of SiO2 per mole of Al2O3, preferably at least 200 moles of SiO2 per mole of Al2O3, more preferably at least 400 moles of SiO2 per mole of Al2O3, or -The zeolite crystals are aluminophosphate zeolite crystals; - Multiple dye molecules, particularly dye molecules, wherein the spatial extent of at least two mutually perpendicular dimensions of each dye molecule is smaller than the pore size, and - A solvent, wherein the solvent is or comprises cyclic siloxanes, perfluorinated solvents, sterically hindered aromatic solvents, crown ethers, triglycerides, 9-ethyl-9-heptyloctadecane, 2,2,4,15,17,17-hexamethyl-7,12-bis(3,5,5-trimethylhexyl)octadecane, 3-heptadecanone, 5-decyl-5-heptyl-2,2-dimethyl, 3-heptadecanol, 5-decyl-5-heptyl-2,2-dimethyl, 2,2,4,10,12,12-hexamethyl-7-(3,5,5-trimethylhexyl)tridecane, 8-hexyl-8-pentylhexadecane, esters, linoleic acid, stearic acid, trans-oleic acid, or combinations thereof; and - The mixture is heated to at least 100°C, preferably at least 120°C, more preferably at least 140°C, to obtain the dye-loaded composite material.

13. The method of claim 12, wherein the method further comprises: - The step of removing water from the solvent before adding the solvent to the mixture to a maximum water content of 0.1% by weight, preferably 0.01% by weight, most preferably 0.001% by weight, and / or - Before adding the plurality of zeolite crystals to the mixture, the plurality of zeolite crystals are dried at a temperature of at least 110°C, preferably at least 130°C, most preferably at least 150°C for at least 2 h, preferably at least 5 h, most preferably at least 8 h.

14. Use of the dye-loaded composite material according to claims 1 to 5, the zeolite-polymer hybrid material according to claims 6 to 8, the light-emitting concentrator according to claims 9 to 10, or the photovoltaic device according to claim 11 in a photovoltaic device.

15. The use according to claim 14, wherein the photovoltaic device is integrated into window glass, greenhouse roof, panel covering photosynthetic plants, or any combination thereof.

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