Perovskite solar cell and perovskite solar module

Abstract

The embodiment of the present application provides a perovskite solar cell and a perovskite solar cell module, the perovskite solar cell comprising: a light absorption layer, an up-conversion layer, a first conductive layer and a second conductive layer for collecting opposite type carriers, and a first transport layer and a second transport layer for transporting opposite type carriers, the first conductive layer being a transparent conductive layer, wherein the first transport layer is arranged between the first conductive layer and the light absorption layer, the second transport layer is arranged between the up-conversion layer and the second conductive layer, and the up-conversion layer is arranged on the side of the light absorption layer away from the first transport layer; the up-conversion layer is a halide perovskite structure member of a light-emitting dopant, and the light absorption layer is a perovskite structure member. The energy conversion efficiency of the perovskite solar cell can be effectively improved.

Description

Technical Field

[0001] This invention relates to the field of solar cell technology, and in particular to a perovskite solar cell and a perovskite solar module. Background Technology

[0002] With the development of solar cells, perovskite solar cells, as a novel concept in solar cells, have gradually become a research hotspot in the field of solar cells due to their superior performance and low cost. Corresponding to the band gap of existing perovskite material systems, the theoretical upper limit of the conversion efficiency of perovskite solar cells is between 30% and 33%.

[0003] To further improve the energy conversion efficiency of perovskite solar cells, existing technologies have introduced an upconversion layer. This upconversion layer can be positioned between the electrode and the carrier transport layer, or it can be positioned on the side of the transparent electrode away from the carrier transport layer. The upconversion layer converts photons with energy below the perovskite bandgap in the solar spectrum into photons with energy above the perovskite bandgap that can be utilized by the absorption layer. This broadens the absorption spectrum range of perovskite solar cells and improves their energy conversion efficiency.

[0004] However, the main material of the upconversion layer is usually a NaYF4 (sodium tetrafluoroethylene ytterbium) system doped with Yb (ytterbium) and Er (erbium), making the upconversion layer an insulator with a wide band gap. When the upconversion layer is placed between the electrode and the carrier transport layer, it can easily affect the transport of carriers from the carrier transport layer to the electrode, thus affecting the electrode's collection of carriers. When the upconversion layer is placed on the side of the transparent electrode away from the carrier transport layer, the transparent electrode has a high resistance, which is not conducive to the electrode's efficient collection of carriers. Both of these placement methods of the upconversion layer can easily affect the electrode's collection of carriers, limiting the improvement of the energy conversion efficiency of perovskite solar cells. Summary of the Invention

[0005] In view of the above problems, embodiments of the present invention are proposed to provide a perovskite solar cell and a corresponding perovskite solar cell module that overcome or at least partially solve the above problems.

[0006] To address the aforementioned problems, this invention discloses a perovskite solar cell, comprising: a light-absorbing layer, an up-conversion layer, a first conductive layer and a second conductive layer for collecting opposite-type charge carriers, and a first transport layer and a second transport layer for transporting opposite-type charge carriers, wherein the first conductive layer is a transparent conductive layer.

[0007] The first transmission layer is disposed between the first conductive layer and the light absorption layer, the second transmission layer is disposed between the upconversion layer and the second conductive layer, and the upconversion layer is disposed on the side of the light absorption layer away from the first transmission layer;

[0008] The upconversion layer is a halide perovskite structure containing luminescent dopants, and the light absorption layer is a perovskite structure.

[0009] Optionally, the lattice mismatch δ between the upconversion layer and the light absorption layer is ≤20%.

[0010] Optionally, the luminescent dopant includes sensitizer ions and activator ions.

[0011] Optionally, the upconversion layer includes a transition layer and an epitaxial layer, wherein the transition layer is disposed between the light-absorbing layer and the epitaxial layer;

[0012] The photoelectric performance parameters of the transition layer near the light absorption layer are the same as those of the light absorption layer, and the photoelectric performance parameters of the transition layer near the epitaxial layer are the same as those of the epitaxial layer.

[0013] Optionally, the thickness of the transition layer is 0-100 nanometers.

[0014] Optionally, the band gap of the upconversion layer is greater than or equal to 2.7 eV.

[0015] Optionally, the thickness of the upconversion layer is less than or equal to 200 micrometers.

[0016] Optionally, the phonon energy of the host material of the upconversion layer is less than or equal to 400 cm⁻¹.

[0017] Optionally, the upconversion layer is obtained by epitaxial growth of the light-absorbing layer;

[0018] The grains of the upconversion layer and the grains of the light-absorbing layer are chemically bonded.

[0019] Optionally, the upconversion layer includes at least one of the following: MAPbCl3 structure, FAPbCl3 structure, CsPbCl3 structure, EAPbCl3 structure, PAPbCl3 structure, BAPbCl3 structure and PEAPbCl3 structure.

[0020] Secondly, embodiments of the present invention also provide a perovskite solar cell module, including the perovskite solar cell described above.

[0021] The embodiments of the present invention have the following advantages:

[0022] In this embodiment of the invention, the upconversion layer can absorb photons that the light-absorbing layer cannot absorb, and can convert the photons into photons that the light-absorbing layer can absorb. This increases the amount of photons absorbed by the light-absorbing layer, resulting in more charge carriers generated by the photons. The first and second conductive layers can then collect more charge carriers, thereby improving the energy conversion efficiency of the perovskite solar cell. Since both the upconversion layer and the light-absorbing layer are perovskite structures, the upconversion layer can have the same or similar crystal structure as the light-absorbing layer. This reduces the charge transport barrier of the upconversion layer and minimizes its impact on the second conductive layer's collection of photogenerated charge carriers from the light-absorbing layer. Furthermore, since the upconversion layer is located between the light-absorbing layer and the second conductive layer, the second conductive layer does not need to be a transparent electrode, resulting in lower resistance. This facilitates efficient charge carrier collection by the second conductive layer, further improving the energy conversion efficiency of the perovskite solar cell. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of a perovskite solar cell according to the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of an upconversion layer according to the present invention;

[0025] Figure 3 This is a schematic diagram of another upconversion layer structure of the present invention.

[0026] Figure label:

[0027] 1-First conductive layer, 2-Light absorption layer, 3-Upconversion layer, 31-Transition layer, 32-Epipolar layer, 33-Main material, 34-Sensitizer ions, 35-Activator ions, 4-Second conductive layer, 51-First transport layer, 52-Second transport layer. Detailed Implementation

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0030] In the description of this invention, it should be understood that the terms "width", "thickness", "upper", "lower", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] One of the core concepts of this invention is to disclose a perovskite solar cell.

[0033] Reference Figure 1 The diagram illustrates a structural schematic of a perovskite solar cell according to the present invention. Specifically, the perovskite solar cell may include: a light-absorbing layer 2, an upconversion layer 3, a first conductive layer 1 and a second conductive layer 4 for collecting opposite-type charge carriers, and a first transport layer 51 and a second transport layer 52 for transporting opposite-type charge carriers. The first conductive layer 1 is a transparent conductive layer. The first transport layer 51 is disposed between the first conductive layer 1 and the light-absorbing layer 2, and the second transport layer 52 is disposed between the upconversion layer 3 and the second conductive layer 4. The upconversion layer 3 is disposed on the side of the light-absorbing layer 2 away from the first transport layer 51. The upconversion layer 3 is a halide perovskite structure containing a light-emitting dopant, and the light-absorbing layer 2 is a perovskite structure.

[0034] In this embodiment of the invention, the upconversion layer 3 can absorb photons that the light absorption layer 2 cannot absorb, and can convert photons into photons that the light absorption layer 2 can absorb. This increases the amount of photons absorbed by the light absorption layer 2, resulting in more charge carriers generated by the photons. The second conductive layer 4 can then collect more charge carriers, thereby improving the energy conversion efficiency of the perovskite solar cell. Since the upconversion layer 3 is a halide perovskite structure and the light absorption layer 2 is a perovskite structure, the upconversion layer 3 can have the same or similar crystal structure as the light absorption layer 2. This reduces the charge transport barrier of the upconversion layer 3 and decreases its impact on the second conductive layer 4's collection of photogenerated charge carriers from the light absorption layer 2. Furthermore, since the upconversion layer 3 is located between the light absorption layer 2 and the second conductive layer 4, the second conductive layer 4 does not need to be a transparent electrode, resulting in lower resistance. This facilitates the efficient collection of charge carriers by the second conductive layer 4, further improving the energy conversion efficiency of the perovskite solar cell.

[0035] In this embodiment of the invention, the first conductive layer 1 is a transparent conductive layer, allowing light waves to pass through it and be absorbed by the light-absorbing layer 2. The first transmission layer 51 can also be a transparent structure, allowing light waves to pass through it and be absorbed by the light-absorbing layer 2. Specifically, after the light-absorbing layer 2 absorbs photons, it can generate carrier pairs of opposite types. One type of carrier can be transported through the first transmission layer 51 to the first conductive layer 1 and collected by the first conductive layer 1, while the other type of carrier can be transported through the second transmission layer 52 to the second conductive layer 4 and collected by the second conductive layer 4.

[0036] Specifically, the first conductive layer 1 and the second conductive layer 4 can be used to collect opposite types of charge carriers. The first conductive layer 1 can have both light transmission and conductivity properties, and can be a transparent conductive structure such as ITO (Indium Tin Oxide) conductive glass, FTO (Fluorine-doped Tin Oxide) conductive glass, or AZO conductive glass (AZOCoating Glass). The second conductive layer 4 can be an opaque metallic conductive structure with low resistance, which is beneficial for the efficient collection of charge carriers. In practical applications, the second conductive layer 4 can also be a transparent conductive structure such as ITO conductive glass, FTO conductive glass, or AZO conductive glass; this embodiment of the invention does not specifically limit this.

[0037] Furthermore, both the first transport layer 51 and the second transport layer 52 can be used to transport charge carriers. The types of charge carriers transported by the first transport layer 51 and the second transport layer 52 are opposite, including electrons and holes. The first transport layer 51 can transport electrons, and the second transport layer 52 can transport holes; or, the first transport layer 51 can transport holes, and the second transport layer 52 can transport electrons. The specific configuration can be determined according to actual needs, and this embodiment of the invention does not impose specific limitations on this.

[0038] Specifically, the upconversion layer 3 can be a halide perovskite structure containing luminescent dopants, and the light absorption layer 2 can be a perovskite structure, so that the upconversion layer 3 and the light absorption layer 2 can have the same or similar crystal structure, which can reduce the influence of the upconversion layer 3 on carrier transport and improve the efficiency of the second conductive layer 4 in collecting carriers.

[0039] Specifically, the halide perovskite structure contains a luminescent dopant, which, under the excitation of the luminescent dopant, enables the luminescence process of the upconversion layer 3.

[0040] Specifically, the light-absorbing layer 2 can be a perovskite structure obtained using light-absorbing materials such as organic-inorganic halide perovskite, all-inorganic perovskite, lead-free perovskite, double perovskite, and ABX3 perovskite (A is an organic amine cation, B is a lead or tin ion, and X is a halide anion or thiocyanate ion).

[0041] Specifically, the upconversion layer 3 also includes a host material 33, which is the main component of the upconversion layer 3. The host material 33 can be a halide perovskite, and the luminescent dopant can be mixed in the host material 33.

[0042] Optionally, the upconversion layer 3 may include at least one of the following: MAPbCl3 structure, FAPbCl3 structure, CsPbCl3 structure, EAPbCl3 structure, PAPbCl3 structure, BAPbCl3 structure and PEAPbCl3 structure.

[0043] In this embodiment of the invention, the upconversion layer 3 can be a MAPbCl3 structure, a FAPbCl3 structure, or a CsPbCl3 structure. It can also be a solid solution structure of MAPbCl3 and FAPbCl3, a solid solution structure of MAPbCl3, FAPbCl3 and CsPbCl3, a solid solution structure of MAPbCl3 and BAPbCl3, a solid solution structure of FAPbCl3 and PEAPbCl3, etc. The specific structure can be modulated according to actual needs, and this embodiment of the invention does not impose any specific limitations on it.

[0044] Optionally, the lattice mismatch δ between the upconversion layer 3 and the light absorption layer 2 is ≤20%. In practical applications, a lattice mismatch δ ≤20% between the upconversion layer 3 and the light absorption layer 2 ensures that the crystal structures of the upconversion layer 3 and the light absorption layer 2 are the same or similar, and also guarantees that the upconversion layer 3 has good crystal quality and structural integrity.

[0045] Furthermore, Where a1 is the lattice constant of the upconversion layer 3 and a2 is the lattice constant of the light absorption layer 2.

[0046] Specifically, the lattice mismatch δ can be 10%, 12%, 15%, or 20%, etc., and can be adjusted according to actual needs. This embodiment of the invention does not impose a specific limitation on this.

[0047] Optionally, the luminescent dopant includes sensitizer ions and activator ions. In practical applications, the sensitizer ions are excited after absorbing photon energy and can transfer the energy to the activator ions. The activator ions can then release photons with higher energy, thereby enabling the luminescence process of the upconversion layer.

[0048] Specifically, such as Figure 2 As shown, after two or more sensitizer ions 34 absorb the energy of photons, the electrons in the sensitizer ions 34 can be excited and transfer the energy to the activator ions 35. The electrons in the activator ions 35 can absorb the energy excited by the electrons in multiple sensitizer ions 34 and transition to a high-energy state. Then, the electrons in the activator ions 35 can transition from the high-energy state back to the low-energy state and release photons. The energy of a single photon released can be greater than the energy of a single photon absorbed by the sensitizer ions 34, thus realizing the upconversion layer 3 luminescence process.

[0049] Specifically, both the sensitizer ion 34 and the activator ion 35 can be transition metal ions or rare earth metal ions. For example, the sensitizer ion 34 can be Yb3+, Er3+ ions, etc., and the activator ion 35 can be Tm3+ (thulium) ion, Ce3+ (cerium) ion, Tb3+ (terbium) ion, Sm3+ (samarium) ion, Eu3+ (europium) ion, Er3+, Ho3+ (holmium) ion, Dy3+ (dysprosium) ion, etc.

[0050] Furthermore, in the upconversion layer 3 system, the host material 33 can serve as an energy transfer medium and provide a matrix lattice for the sensitizer ions 34 and the activator ions 35.

[0051] like Figure 3 As shown, the upconversion layer 3 may include a transition layer 31 and an epitaxial layer 32. The transition layer 31 may be disposed between the light absorption layer 2 and the epitaxial layer 32. The photoelectric performance parameters of the side of the transition layer 31 near the light absorption layer 2 may be the same as those of the light absorption layer 2, and the photoelectric performance parameters of the side of the transition layer 31 near the epitaxial layer 32 may be the same as those of the epitaxial layer 32.

[0052] In this embodiment of the invention, the transition layer 31 is disposed between the light absorption layer 2 and the epitaxial layer 32. Moreover, in the direction from the light absorption layer 2 to the epitaxial layer 32, the photoelectric performance parameters of the transition layer 31 can gradually transition from being the same as those of the light absorption layer 2 to being the same as those of the epitaxial layer 32, which is beneficial for the transport of charge carriers to the second conductive layer 4 and their collection by the second conductive layer 4.

[0053] Specifically, the photoelectric performance parameters may include: lattice constant, valence band top and conduction band bottom, etc. The side of the transition layer 31 near the light absorption layer 2 has the same lattice constant, the same valence band top and the same conduction band bottom as the side of the light absorption layer 2. The side of the transition layer 31 near the epitaxial layer 32 has the same lattice constant, the same valence band top and the same conduction band bottom as the side of the epitaxial layer 32.

[0054] Furthermore, due to the presence of the transition layer 31, the change in the lattice constant between the light absorption layer 2 and the epitaxial layer 32 is gradual, which can alleviate lattice distortion and lattice stress, improve the stability of the light absorption layer 2 and the upconversion layer 3, and thus improve the stability of the perovskite solar cell.

[0055] Specifically, the band gaps and electronic energy levels of the upconversion layer 3 and the light absorption layer 2 are different. Under the action of the transition layer 31, the electronic energy levels and band gaps between the light absorption layer 2 and the epitaxial layer 32 can also be gradually transitioned. Moreover, during the process of charge carriers transporting from the light absorption layer 2 through the upconversion layer 3 to the second conductive layer 4, there is a gradually changing potential barrier, which is more conducive to the transport of charge carriers to the second conductive layer 4 and their collection by the second conductive layer 4.

[0056] Specifically, the transition layer 31 can be a halide perovskite structure with "soft lattice" characteristics, which can achieve a better crystal structure transition.

[0057] Optionally, the thickness of the transition layer 31 is 0-100 nanometers. In practical applications, the thickness of the transition layer 31 can be adjusted, which can improve the adaptability of the upconversion layer 3.

[0058] Specifically, when the thickness of the transition layer 31 is 0, the lattice mismatch δ between the light-absorbing layer 2 and the epitaxial layer 32 can be less than or equal to 20%. When the thickness of the transition layer 31 is thicker, the gradient effect from the light-absorbing layer 2 to the epitaxial layer 32 is better, which is more conducive to the transport of charge carriers to the second conductive layer 4 and their collection by the second conductive layer 4, resulting in higher energy conversion efficiency of the perovskite solar cell.

[0059] Optionally, the band gap of the upconversion layer 3 can be larger than the band gap of the light absorption layer 2.

[0060] In this embodiment of the invention, the band gap of the upconversion layer 3 is larger than that of the light absorption layer 2, which can avoid the competition between the upconversion layer 3 and the light absorption layer 2, and facilitate the light absorption layer 2 to absorb photons more efficiently, thereby generating more charge carriers and improving the energy conversion efficiency of the perovskite solar cell.

[0061] Optionally, the band gap of the upconversion layer 3 can be greater than or equal to 2.7 eV. In practical applications, the band gap of the upconversion layer 3 can be greater than or equal to 2.7 eV, which can effectively ensure that the band gap of the upconversion layer 3 is greater than the band gap of the light absorption layer 2.

[0062] Specifically, the host material 33 of the upconversion layer 3 can be a halide perovskite, and the band gap of the host material 33 can be greater than or equal to 2.7 eV.

[0063] Optionally, the thickness of the upconversion layer 3 can be less than or equal to 200 micrometers. In practical applications, when the thickness of the upconversion layer 3 is less than or equal to 200 micrometers, it can be ensured that the second conductive layer 4 effectively collects the charge carriers generated in the light absorption layer 2.

[0064] Specifically, the upconversion layer 3 can be obtained based on the light absorption layer 2, and can have carrier transport performance close to that in the light absorption layer 2. In this way, the photogenerated carriers generated in the light absorption layer 2 can also have a long diffusion length in the upconversion layer 3. In the embodiment of the present invention, limiting the thickness of the upconversion layer 3 can ensure that the second conductive layer 4 effectively collects the carriers generated in the light absorption layer 2.

[0065] Optionally, the phonon energy of the main material 33 of the upconversion layer 3 can be less than or equal to 400 cm⁻¹ (wave number: the reciprocal of wavelength λ, i.e., the number of waves contained in 1 cm). In practical applications, having a phonon energy of less than or equal to 400 cm⁻¹ in the main material 33 of the upconversion layer 3 can prevent the phonon energy of the main material 33 from being too high, thereby preventing excessively strong interactions between photons and phonons within the material. This is beneficial for improving the conversion efficiency of photons converted by the upconversion layer 3, and thus increasing the amount of photons absorbed by the light absorption layer 2.

[0066] Specifically, the host material 33 of the upconversion layer 3 can be a halide perovskite, and the phonon energy of the host material 33 can be less than or equal to 400 cm⁻¹.

[0067] Optionally, the upconversion layer 3 is obtained by epitaxial growth of the light absorption layer 2; the grains of the upconversion layer 3 and the grains of the light absorption layer 2 are chemically bonded together.

[0068] In this embodiment of the invention, the upconversion layer 3 can be an in-situ epitaxial upconversion layer 3 obtained by epitaxial growth of the light absorption layer 2, so that the upconversion layer 3 and the light absorption layer 2 can have the same crystal structure and crystal orientation. Moreover, the grains of the upconversion layer 3 and the grains of the light absorption layer 2 can be chemically bonded, so that the upconversion layer 3 and the light absorption layer 2 can have the same or similar carrier transport performance. The photogenerated carriers generated by the light absorption layer 2 can be efficiently transported to the second conductive layer 4 and collected by the second conductive layer 4, which can improve the carrier collection efficiency.

[0069] Specifically, epitaxial growth refers to the upconversion layer 3 being obtained based on the light absorption layer 2, having the same crystal structure and a perfect or near-perfect interface structure as the light absorption layer 2.

[0070] Furthermore, when the light-absorbing layer 2 is a single-crystal perovskite, the upconversion layer 3 can also be a single-crystal layer. The two single-crystal layers are bonded by chemical bonds and have the same crystal structure and orientation. When the light-absorbing layer 2 is a polycrystalline perovskite, the upconversion layer 3 can also be a polycrystalline layer. At the interface between the light-absorbing layer 2 and the upconversion layer 3, the adjacent grains of the light-absorbing layer 2 and the upconversion layer 3 exhibit epitaxial characteristics. That is, the grains of the upconversion layer 3 grow by continuing the crystal structure and orientation corresponding to the grains of its adjacent light-absorbing layer 2. At the interface, the grains of the upconversion layer 3 and the grains of the adjacent light-absorbing layer 2 have the same crystal structure and orientation, and the grains can be bonded by chemical bonds.

[0071] Specifically, the epitaxial growth methods include at least one of vapor phase deposition epitaxy and solid-state reaction epitaxy. In practical applications, vapor phase deposition epitaxy can be molecular beam epitaxy, while solid-state reaction epitaxy can specifically include: based on the characteristics of perovskite materials that can undergo ion migration and solid-state reactions, a light absorption layer 2 and an upconversion layer 3 are pre-prepared, and the two are bonded together and heated. Through a solid-state reaction, the crystal lattice of the two is bonded, thus completing the preparation of the epitaxial upconversion layer 3.

[0072] Specifically, the fabrication methods of the perovskite solar cells in the embodiments of the present invention may include the following:

[0073] In the first configuration, the first conductive layer 1 can be an FTO conductive glass structure, the first transport layer 51 can be a SnO2 (tin dioxide) electron transport layer with a thickness of 60 nm, the light absorption layer 2 can be a FAPbI3 (formimide lead iodide) perovskite layer with a thickness of 1000 nm and a band gap of 1.48 eV, the upconversion layer 3 can be prepared on the light absorption layer 2 using molecular beam epitaxy, with a thickness of 1000 nm and a band gap of 3.02 eV, the second transport layer 52 can be a Spiro-OMeTAD (solid electrolyte) hole transport layer with a thickness of 100 nm, and the second conductive layer 4 can be an Ag (silver) structure with a thickness of 120 nm.

[0074] In this embodiment, the lattice constant of FAPbCl3 can be (Å), the lattice constant of FAPbI3 can be The lattice mismatch between the two is δ = 12.24%; the phonon energy of FAPbCl3 can be 200 cm⁻¹.

[0075] The second type of perovskite solar cell can include a first cell structure and a second cell structure. The first cell structure can consist of a first conductive layer 1, a first transport layer 51, and a light-absorbing layer 2. The first conductive layer 1 can be an ITO conductive glass structure; the first transport layer 51 can be a NiO (nickel oxide) hole transport layer with a thickness of 200 nanometers; the light-absorbing layer 2 can be a CsPbI3 (cesium triiodide lead oxide) perovskite layer with a thickness of 900 nanometers and a band gap of 1.73 eV. The second cell structure can consist of an upconversion layer 3, a second transport layer 52, and a second conductive layer 4. The second conductive layer 4 can be an ITO conductive glass structure, the second transport layer 52 is a PC61BM ((6,6)phenyl-C61-butyrate methyl ester) electron transport layer with a thickness of 100 nanometers; the upconversion layer 3 can be a CsPbCl3 (cesium trichloroleadate) (17%-Er 3+, 1%-Tm 3+) upconversion layer 3 with a band gap of 2.99 eV and a thickness of 2000 nanometers.

[0076] Specifically, the light-absorbing layer 2 and the upconversion layer 3 are brought into contact, bonding the first and second battery components together. The entire assembly is then heated at 120°C for 1 hour in an inert atmosphere. Due to the migration of iodine and chloride ions, a solid-state reaction occurs between the light-absorbing layer 2 and the upconversion layer 3, allowing the first and second battery components to be joined together to form a perovskite solar cell. Furthermore, due to the gradient of ion migration, the upconversion layer 3 may include an epitaxial layer 32 and a transition layer 31. The transition layer 31, with a thickness of approximately 10-30 nanometers, can be formed between the light-absorbing layer 2 and the epitaxial layer 32.

[0077] In this embodiment, the lattice constant of CsPbCl3 can be... The lattice constant of CsPbI3 can be The lattice mismatch between the two is δ = 10.6%; the phonon energy of CsPbCl3 can be 150 cm⁻¹.

[0078] The third type involves the following: the first conductive layer 1 can be an FTO conductive glass structure; the first transport layer 51 can be a SnO2 electron transport layer with a thickness of 60 nanometers; the light absorption layer 2 can be a MAPbI3 perovskite layer with a thickness of 1000 nanometers and a band gap of 1.59 eV; the upconversion layer 3 can be prepared on the light absorption layer 2 using molecular beam epitaxy, with a thickness of 1000 nanometers and a band gap of 3.04 eV; the second transport layer 52 can be a Spiro-OMeTAD hole transport layer with a thickness of 100 nanometers; and the second conductive layer 4 can be an Ag structure with a thickness of 120 nanometers.

[0079] In this embodiment, the lattice constant of MAPbCl3 can be (Å), the lattice constant of MAPbI3 can be The lattice mismatch between the two is δ = 10.3%; the phonon energy of FAPbCl3 can be 200 cm⁻¹.

[0080] Fourthly, the first conductive layer 1 can be an FTO conductive glass structure, the first transport layer 51 can be a SnO2 electron transport layer with a thickness of 60 nm, the light absorption layer 2 can be a FAPbI3 perovskite layer with a thickness of 1000 nm and a band gap of 1.48 eV, the upconversion layer 3 can be prepared on the light absorption layer 2 using molecular beam epitaxy, the upconversion layer 3 can have a thickness of 1000 nm and a band gap of 3.02 EV, the material of the upconversion layer 3 can be a solid solution of MAPbCl3 and FAPbCl3 MAxFA1-x PbCl3 (the value of x can be continuously varied between 0 and 1), and the lattice constant of the upconversion layer 3 can also be continuously varied, the second transport layer 52 can be a Spiro-OMeTAD hole transport layer with a thickness of 100 nm, and the second conductive layer 4 can be an Ag structure with a thickness of 120 nm.

[0081] In this embodiment, the lattice mismatch δ between the upconversion layer 3 and the light absorption layer 2 is 10.3%-12.24%.

[0082] Fifthly, the first conductive layer 1 can be an FTO conductive glass structure, the first transport layer 51 can be a SnO2 electron transport layer with a thickness of 60 nanometers, the light absorption layer 2 can be a FAPbI3 perovskite layer with a thickness of 1000 nanometers and a band gap of 1.48 eV, the upconversion layer 3 can be prepared on the light absorption layer 2 using molecular beam epitaxy, the upconversion layer 3 can be 1000 nanometers thick, and the material of the upconversion layer 3 can be a solid solution of EAPbI3 (ethylamine lead iodide) and FAPbCl3, the second transport layer 52 can be a Spiro-OMeTAD hole transport layer with a thickness of 100 nanometers, and the second conductive layer 4 can be an Ag (silver) structure with a thickness of 120 nanometers.

[0083] In this embodiment, the lattice constant of EAPbI3 can be (Å), by adjusting the solid solution ratio of EAPbI3 and FAPbCL3, the lattice mismatch between the upconversion layer 3 and the light absorption layer 2 can reach δ = 20%.

[0084] Specifically, when the upconversion layer 3 is obtained by vapor deposition epitaxy, sensitizer ions 34 and activator ions 35 can be deposited simultaneously with the host material 33 to form a rare-earth-doped epitaxial upconversion layer 3. When the upconversion layer 3 is obtained by solid-state reaction epitaxy, the solid-state reaction occurs between the pre-prepared light-absorbing layer 2 and the upconversion layer 3. During the pre-preparation of the upconversion layer 3, sensitizer ions 34 and activator ions 35 can be incorporated into the upconversion layer 3. Then, the light-absorbing layer 2 and the upconversion layer 3 can be bonded together through a solid-state reaction to complete the preparation of the epitaxial upconversion layer 3.

[0085] In this embodiment of the invention, an upconversion layer 3 using wide-bandgap halide perovskite as the host material 33 is specifically disclosed, and a perovskite solar cell using the upconversion layer 3 is also disclosed. Using wide-bandgap halide perovskite as the host material 33 of the upconversion layer 3 can meet the requirements of the upconversion layer 3 while avoiding interference with the transport and collection of photogenerated carriers, thereby improving the energy conversion efficiency of the perovskite solar cell.

[0086] The perovskite solar cells described in the embodiments of the present invention have at least the following advantages:

[0087] In this embodiment of the invention, the upconversion layer can absorb photons that the light-absorbing layer cannot absorb, and can convert the photons into photons that the light-absorbing layer can absorb. This increases the amount of photons absorbed by the light-absorbing layer, resulting in more charge carriers generated by the photons. The first and second conductive layers can then collect more charge carriers, thereby improving the energy conversion efficiency of the perovskite solar cell. Since the lattice mismatch δ ≤ 20% between the upconversion layer and the light-absorbing layer allows the upconversion layer to have the same or similar crystal structure as the light-absorbing layer. This reduces the charge transport barrier of the upconversion layer and minimizes its impact on the second conductive layer's collection of photogenerated charge carriers from the light-absorbing layer. Furthermore, since the upconversion layer is located between the light-absorbing layer and the second conductive layer, the second conductive layer does not need to be a transparent electrode, resulting in lower resistance. This facilitates efficient charge carrier collection by the second conductive layer, further improving the energy conversion efficiency of the perovskite solar cell.

[0088] Secondly, embodiments of the present invention also disclose a perovskite solar cell module, which may specifically include the perovskite solar cell described above.

[0089] The perovskite solar cell module described in this embodiment of the invention has at least the following advantages:

[0090] In this embodiment of the invention, the upconversion layer can absorb photons that the light-absorbing layer cannot absorb, and can convert the photons into photons that the light-absorbing layer can absorb. This increases the amount of photons absorbed by the light-absorbing layer, resulting in more charge carriers generated by the photons. The first and second conductive layers can then collect more charge carriers, thereby improving the energy conversion efficiency of the perovskite solar cell. Since the lattice mismatch δ ≤ 20% between the upconversion layer and the light-absorbing layer allows the upconversion layer to have the same or similar crystal structure as the light-absorbing layer. This reduces the charge transport barrier of the upconversion layer and minimizes its impact on the second conductive layer's collection of photogenerated charge carriers from the light-absorbing layer. Furthermore, since the upconversion layer is located between the light-absorbing layer and the second conductive layer, the second conductive layer does not need to be a transparent electrode, resulting in lower resistance. This facilitates efficient charge carrier collection by the second conductive layer, further improving the energy conversion efficiency of the perovskite solar cell.

[0091] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0092] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0093] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0094] The present invention has provided a detailed description of a perovskite solar cell and a perovskite solar cell module. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A perovskite solar cell, characterized in that, include: The system comprises a light-absorbing layer, an upconversion layer, a first conductive layer and a second conductive layer for collecting opposite-type charge carriers, and a first transport layer and a second transport layer for transporting opposite-type charge carriers. The first conductive layer is a transparent conductive layer. The first transmission layer is disposed between the first conductive layer and the light absorption layer, the second transmission layer is disposed between the upconversion layer and the second conductive layer, and the upconversion layer is disposed on the side of the light absorption layer away from the first transmission layer; the side of the first conductive layer opposite to the first transmission layer has a light-receiving surface. The upconversion layer is a halide perovskite structure containing luminescent dopants, and the light absorption layer is a perovskite structure.

2. The perovskite solar cell according to claim 1, characterized in that, The lattice mismatch between the upconversion layer and the light absorption layer is δ≤20%.

3. The perovskite solar cell according to claim 1, characterized in that, The luminescent dopant includes sensitizer ions and activator ions.

4. The perovskite solar cell according to claim 1, characterized in that, The upconversion layer includes a transition layer and an epitaxial layer, wherein the transition layer is disposed between the light-absorbing layer and the epitaxial layer; The photoelectric performance parameters of the transition layer near the light absorption layer are the same as those of the light absorption layer, and the photoelectric performance parameters of the transition layer near the epitaxial layer are the same as those of the epitaxial layer.

5. The perovskite solar cell according to claim 4, characterized in that, The thickness of the transition layer is 0-100 nanometers.

6. The perovskite solar cell according to claim 1, characterized in that, The band gap of the upconversion layer is greater than or equal to 2.7 eV.

7. The perovskite solar cell according to claim 1, characterized in that, The thickness of the upconversion layer is less than or equal to 200 micrometers.

8. The perovskite solar cell according to claim 1, characterized in that, The phonon energy of the host material of the upconversion layer is less than or equal to 400 cm⁻¹.

9. The perovskite solar cell according to claim 1, characterized in that, The upconversion layer is obtained by epitaxial growth of the light absorption layer; The grains of the upconversion layer and the grains of the light absorption layer are chemically bonded together.

10. The perovskite solar cell according to claim 1, characterized in that, The upconversion layer includes at least one of the following: MAPbCl3 structure, FAPbCl3 structure, CsPbCl3 structure, EAPbCl3 structure, PAPbCl3 structure, BAPbCl3 structure and PEAPbCl3 structure.

11. A perovskite solar module, characterized in that, Including the perovskite solar cell according to any one of claims 1 to 10.

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