Perovskite solar cell

Abstract

The utility model provides a perovskite solar cell, and particularly relates to the technical field of solar cells. The perovskite solar cell comprises a conductive glass substrate, an electron transport layer, a perovskite light absorption layer, a molecular modification layer, a hole transport layer and a metal electrode, the molecular modification layer comprises a benzyltriethylammonium one-dimensional lead halide structure. A molecular modification layer is arranged on a perovskite light absorption layer or the perovskite light absorption layer and the molecular modification layer are integrated into a perovskite composite light absorption layer, so that a benzyltriethylammonium one-dimensional lead halide structure is successfully introduced. And a benzyltriethylammonium one-dimensional lead halide structure in the molecular modification layer is used as a hydrophobic barrier, so that water and oxygen erosion can be effectively blocked, a dimensional mutual dissolution reaction with the three-dimensional perovskite can be avoided, and the environmental stability of the device is remarkably improved. The photoelectric conversion efficiency of the device is improved in a breakthrough manner, and the device is endowed with excellent operation stability and process repeatability.

Description

Technical Field

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

[0002] Perovskite solar cells, with their unique photoelectric properties (tunable bandgap, high absorption coefficient) and manufacturing advantages (low-temperature solution processing, low raw material costs), have increased certified efficiency to 27.0% over the past decade, demonstrating industrialization potential that surpasses traditional crystalline silicon technology. However, this technology still faces multi-dimensional scientific challenges that require breakthroughs.

[0003] From the perspective of intrinsic material properties, lattice defects (such as surface dangling bonds and grain boundary dislocations) formed during solution fabrication exacerbate nonradiative recombination of charge carriers, severely limiting the open-circuit voltage and fill factor of devices. Simultaneously, the chemical decomposition mechanism of perovskite materials under environmental water and oxygen erosion, and the migration behavior of halide ions under operating conditions, constitute fundamental challenges to the long-term stability of devices. It is noteworthy that existing dimensional engineering strategies exhibit significant technical contradictions in addressing these issues: while two-dimensional / three-dimensional heterostructures can enhance stability through quantum confinement effects, the mixed dimensional phase transitions formed by spontaneous phase separation at the heterostructure interface reconstruct ion diffusion paths, accelerating the degradation of the active layer; while one-dimensional structure designs can alleviate mechanical stress through lattice matching, the breakage of charge carrier migration channels and interface energy level mismatch lead to an increase in charge transport barriers, forming novel recombination centers.

[0004] This antagonistic relationship between material dimensional control and photoelectric properties essentially reflects the deep contradiction between structural stability and carrier transport dynamics within the perovskite system. Constructing multi-scale structures that can both suppress ion migration and maintain efficient charge transport has become a key technological bottleneck in overcoming the current challenge of balancing efficiency and stability.

[0005] In view of the above, this utility model is hereby proposed. Utility Model Content

[0006] One of the objectives of this invention is to provide a perovskite solar cell to solve at least one of the aforementioned technical problems in the prior art.

[0007] In order to achieve the above-mentioned objectives of this utility model, the following technical solution is adopted:

[0008] The first aspect of this utility model provides a perovskite solar cell, comprising a layered conductive glass substrate, an electron transport layer, a perovskite light-absorbing layer, a molecular modification layer, a hole transport layer, and a metal electrode.

[0009] The molecular modification layer includes a benzyltriethylammonium one-dimensional lead halide structure.

[0010] Furthermore, the perovskite solar cell includes a conductive glass substrate, and an electron transport layer, a perovskite light-absorbing layer, a molecular modification layer, a hole transport layer, and a metal electrode sequentially stacked on the conductive glass substrate;

[0011] The molecular modification layer includes a benzyltriethylammonium one-dimensional lead halide structure.

[0012] Furthermore, the perovskite solar cell includes a conductive glass substrate, and a hole transport layer, a perovskite light-absorbing layer, a molecular modification layer, an electron transport layer, and a metal electrode sequentially stacked on the conductive glass substrate;

[0013] The molecular modification layer includes a benzyltriethylammonium one-dimensional lead halide structure.

[0014] Furthermore, the benzyltriethylammonium one-dimensional lead halide structure is formed by benzyltriethylammonium halide and lead halide.

[0015] The general formula of the one-dimensional lead halide structure of benzyltriethylammonium is CMX3; where C is benzyltriethylammonium ion and M is Pb. 2+ Lead ions, where X is a halide ion;

[0016] Preferably, the halide ion includes Cl. - ,Br - and I - At least one of them.

[0017] Furthermore, the conductive glass substrate is FTO.

[0018] Preferably, the electron transport layer is made of TiO2 or SnO2.

[0019] Preferably, the hole transport layer is made of Spiro-OMeTAD material.

[0020] Preferably, the metal electrode is made of Ag or Au.

[0021] Furthermore, the perovskite light-absorbing layer is made of an ABX3 type compound;

[0022] In this system, A is a monovalent organic cation, B is a divalent metal ion, and X is a halide ion.

[0023] Furthermore, the monovalent organic cation includes MA. + FA + Cs + and K + At least one of them.

[0024] Preferably, the divalent metal ion includes Pb. 2+ and / or Sn2+ .

[0025] Preferably, the halide ion includes Cl. - ,Br - and I - At least one of them.

[0026] Furthermore, the thickness of the electron transport layer is 10-200 nm.

[0027] Preferably, the thickness of the perovskite light-absorbing layer is 100-1000 nm.

[0028] Preferably, the thickness of the molecular modification layer is 1-50 nm.

[0029] Preferably, the thickness of the hole transport layer is 50-300 nm.

[0030] Preferably, the thickness of the metal electrode is 80-200 nm.

[0031] The second aspect of this utility model provides a method for preparing the perovskite solar cell, which involves sequentially preparing an electron transport layer, a perovskite light-absorbing layer, a molecular modification layer, a hole transport layer, and a metal electrode on a conductive glass substrate to obtain a perovskite solar cell.

[0032] The molecular modification layer is prepared by first coating the benzyltriethylammonium halide solution onto the perovskite light-absorbing layer, followed by a first heat treatment to obtain the molecular modification layer.

[0033] Further, the concentration of the benzyltriethylammonium halide solution is 0.1–10 mg / mL, preferably 0.5–5 mg / mL.

[0034] Preferably, the solvent in the benzyltriethylammonium halide solution includes at least one of acetonitrile, isopropanol, methanol, ethanol, dimethoxyethanol, and chloroform.

[0035] Preferably, the temperature of the first heat treatment is 100-150°C and the time is 2-60 min.

[0036] Preferably, the first coating method is spin coating.

[0037] Preferably, the spin coating speed is 3000-6000 rpm and the time is 20-60 s.

[0038] Furthermore, the perovskite light-absorbing layer is prepared by: coating a perovskite precursor solution onto an electron transport layer via a second coating, followed by a second heat treatment to obtain the perovskite light-absorbing layer.

[0039] Preferably, the solvent in the perovskite precursor solution includes at least one of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, γ-butyrolactone, and 2-mercaptoethanol.

[0040] Preferably, the concentration of the perovskite precursor solution is 1.0 to 1.7 M.

[0041] Preferably, the temperature of the second heat treatment is 100-150°C and the time is 10-60 min.

[0042] Preferably, the second coating includes spin coating.

[0043] Preferably, the spin coating speed is 3000-6000 rpm and the time is 20-60 s.

[0044] Preferably, the thickness of the perovskite light-absorbing layer is 100–1000 nm.

[0045] The third aspect of this utility model provides another perovskite solar cell, which uses a perovskite composite light-absorbing layer to replace the perovskite light-absorbing layer and molecular modification layer in the perovskite solar cell structure described in the first aspect.

[0046] The perovskite composite light-absorbing layer includes a one-dimensional lead halide structure of perovskite and benzyltriethylammonium.

[0047] The fourth aspect of this utility model provides a method for preparing the perovskite composite light-absorbing layer as follows: an electron transport layer, a perovskite composite light-absorbing layer, a hole transport layer and a metal electrode are sequentially prepared on a conductive glass substrate to obtain a perovskite solar cell.

[0048] The perovskite composite light-absorbing layer is prepared by adding benzyltriethylammonium halide to a perovskite precursor solution and mixing them evenly to obtain a perovskite composite solution; coating the perovskite composite solution onto the electron transport layer in a third process, followed by a third heat treatment to obtain the perovskite composite light-absorbing layer.

[0049] Furthermore, in the perovskite composite solution, the concentration of the benzyltriethylammonium halide solution is 0.1–10 mg / mL, preferably 0.2–5 mg / mL.

[0050] Preferably, the solvent in the perovskite precursor solution includes at least one of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, γ-butyrolactone, and 2-mercaptoethanol.

[0051] Preferably, the temperature of the third heat treatment is 100-150°C and the time is 10-60 min.

[0052] Preferably, the third coating method is spin coating.

[0053] Preferably, the spin coating speed is 3000-6000 rpm and the time is 20-60 s.

[0054] Preferably, the thickness of the perovskite composite light-absorbing layer is 100–1000 nm.

[0055] Compared with the prior art, the present invention has at least the following beneficial effects:

[0056] This invention provides a perovskite solar cell that successfully introduces a benzyltriethylammonium one-dimensional lead halide structure by setting a molecular modification layer on the perovskite light-absorbing layer or by integrating the perovskite light-absorbing layer with the molecular modification layer into a perovskite composite light-absorbing layer. The benzyltriethylammonium one-dimensional lead halide structure in the molecular modification layer acts as a hydrophobic barrier, effectively blocking water and oxygen erosion and preventing dimensional miscibility reactions with the three-dimensional perovskite, significantly improving the device's environmental stability. In the perovskite composite light-absorbing layer, a continuous one-dimensional network structure is self-organized at the grain boundaries, reducing grain boundary dislocation density and suppressing ion migration through lattice anchoring. Simultaneously, the benzyltriethylammonium one-dimensional lead halide structure constructs a cross-dimensional charge transport channel through a π-π conjugated framework, simultaneously utilizing the N atoms at the molecular ends to combine with uncoordinated lead defects on the perovskite surface, achieving a dual gain of optimized carrier transport mechanics and non-radiative recombination suppression. This multi-target modulation at the molecular scale ultimately achieves a breakthrough improvement in the device's photoelectric conversion efficiency and endows it with excellent operational stability and process repeatability. Attached Figure Description

[0057] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0058] Figure 1 This is a schematic diagram of the structure of the perovskite solar cell provided in Embodiment 1 of this utility model;

[0059] Figure 2 This is a schematic diagram of the structure of the perovskite solar cell provided in Embodiment 2 of this utility model;

[0060] Figure 3 This is a schematic diagram of the structure of the perovskite solar cell provided in Embodiment 3 of this utility model;

[0061] Figure 4 This is a schematic diagram of the structure of the perovskite solar cell provided in Embodiment 4 of this utility model;

[0062] Figure 5 This is a current-voltage curve of the perovskite solar cell prepared in Example 5 of this utility model;

[0063] Figure 6 This is a comparison diagram of the stability of perovskite solar cells prepared in Example 5 and Comparative Example 1 of this utility model;

[0064] Figure 7 This is a current-voltage curve of the perovskite solar cell prepared in Example 6 of this utility model;

[0065] Figure 8 This is a current-voltage curve of the perovskite solar cell prepared in Example 7 of this utility model;

[0066] Figure 9 This is a current-voltage curve of the perovskite solar cell prepared in Example 8 of this utility model;

[0067] Figure 10 The current-voltage curve of the perovskite solar cell prepared in Example 9 of this utility model is shown.

[0068] Figure 11 This is a current-voltage curve of the perovskite solar cell prepared in Embodiment 10 of this utility model.

[0069] Figure 12 This is a current-voltage curve of the perovskite solar cell prepared in Embodiment 11 of this utility model;

[0070] Figure 13 This is a current-voltage curve of the perovskite solar cell prepared in Embodiment 12 of this utility model;

[0071] Figure 14 This is a current-voltage curve of the perovskite solar cell prepared in Embodiment 13 of this utility model;

[0072] Figure 15 A schematic diagram of the structure of the perovskite solar cell provided in Comparative Example 1 of this utility model;

[0073] Figure 16 The current-voltage curve of the perovskite solar cell prepared in Comparative Example 1 of this invention is shown.

[0074] Figure 17 This is a SEM image of the perovskite composite light-absorbing layer prepared in Example 10 of this utility model;

[0075] Figure 18 SEM image of the perovskite light-absorbing layer prepared in Comparative Example 1 of this invention;

[0076] Figure 19In the diagram, a and b are both one-dimensional lead halide structures of benzyltriethylammonium; Figure 19 In the diagram, c represents the simulated XRD pattern of the one-dimensional lead halide structure of benzyltriethylammonium; Figure 19 In the figure, d represents the simulated XRD pattern of the benzyltriethylammonium one-dimensional lead halide structure and the XRD pattern of the perovskite composite light-absorbing layer.

[0077] Icons: 100 - Conductive glass substrate; 200 - Electron transport layer; 300 - Perovskite light-absorbing layer; 400 - Molecular modification layer; 500 - Hole transport layer; 600 - Metal electrode; 700 - Perovskite composite light-absorbing layer. Detailed Implementation

[0078] The embodiments and examples of this utility model will be described in detail below. However, those skilled in the art will understand that the following embodiments and examples are only for illustrating this utility model and should not be considered as limiting the scope of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the protection scope of this utility model.

[0079] The term "perovskite solar cell" or "perovskite battery" as used in this utility model includes, but is not limited to, conventional perovskite cells, conventional perovskite modules, inverted perovskite cells, inverted perovskite modules, small-area perovskite cells, small-area perovskite modules, single-junction perovskite cells, single-junction perovskite modules, perovskite-organic tandem cells, perovskite-organic tandem modules, perovskite-perovskite tandem cells, perovskite-perovskite tandem modules, perovskite-crystalline silicon tandem cells, perovskite-crystalline silicon tandem modules, perovskite-copper indium gallium tin tandem cells, and perovskite-copper indium gallium tin tandem modules.

[0080] The first aspect of this utility model provides a perovskite solar cell, including a conductive glass substrate 100, an electron transport layer 200, a perovskite light-absorbing layer 300, a molecular modification layer 400, a hole transport layer 500, and a metal electrode 600.

[0081] The molecular modification layer 400 includes a benzyltriethylammonium one-dimensional lead halide structure.

[0082] In one embodiment of the present invention, the perovskite solar cell includes a conductive glass substrate 100, and an electron transport layer 200, a perovskite light-absorbing layer 300, a molecular modification layer 400, a hole transport layer 500, and a metal electrode 600 sequentially stacked on the conductive glass substrate 100.

[0083] The molecular modification layer 400 includes a benzyltriethylammonium one-dimensional lead halide structure.

[0084] In another embodiment of the present invention, the perovskite solar cell includes a conductive glass substrate 100, and a hole transport layer 500, a perovskite light-absorbing layer 300, a molecular modification layer 400, an electron transport layer 200 and a metal electrode 600 sequentially stacked on the conductive glass substrate 100.

[0085] The molecular modification layer 400 includes a benzyltriethylammonium one-dimensional lead halide structure.

[0086] The third aspect of this utility model provides another perovskite solar cell, which uses a perovskite composite light-absorbing layer 700 to replace the perovskite light-absorbing layer 300 and molecular modification layer 400 in the perovskite solar cell structure described in the first aspect.

[0087] The perovskite composite light-absorbing layer 700 includes a one-dimensional lead halide structure of perovskite and benzyltriethylammonium.

[0088] The perovskite solar cell provided by this utility model successfully introduces a benzyltriethylammonium one-dimensional lead halide structure by setting a molecular modification layer 400 on the perovskite light-absorbing layer 300 or a perovskite composite light-absorbing layer 700 that integrates the perovskite light-absorbing layer 300 and the molecular modification layer 400.

[0089] The benzyltriethylammonium one-dimensional lead halide structure in the molecular modification layer 400 acts as a hydrophobic barrier, effectively blocking water and oxygen erosion and avoiding dimensional miscibility with the three-dimensional perovskite, thus significantly improving the environmental stability of the device.

[0090] The perovskite composite light-absorbing layer 700 has a π-π conjugated system, which is beneficial to charge transport between interfaces and improves the photoelectric conversion efficiency of the device. At the same time, the N atoms in this molecule can interact with the surface defects of the perovskite light-absorbing layer 300, thereby suppressing carrier recombination and further improving the device efficiency.

[0091] Furthermore, the benzyltriethylammonium one-dimensional lead halide structure is formed by benzyltriethylammonium halide and lead halide.

[0092] The general formula of the one-dimensional lead halide structure of benzyltriethylammonium is CMX3; where C is benzyltriethylammonium ion and M is Pb. 2+ Lead ions, where X is a halide ion.

[0093] Preferably, the halide ion includes Cl. - ,Br - and I - At least one of them.

[0094] Furthermore, the conductive glass substrate 100 is FTO.

[0095] FTO glass, short for Fluorine-doped Tin Oxide glass, is a semiconductor material. It achieves conductivity by depositing a thin film of fluorine-doped tin dioxide onto the surface of ordinary glass.

[0096] Preferably, the electron transport layer 200 is made of TiO2 or SnO2.

[0097] Preferably, the hole transport layer 500 is made of Spiro-OMeTAD. Spiro-OMeTAD is 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene.

[0098] Preferably, the metal electrode 600 is made of Ag or Au.

[0099] Furthermore, the perovskite light-absorbing layer 300 is made of an ABX3 type compound;

[0100] In this system, A is a monovalent organic cation, B is a divalent metal ion, and X is a halide ion.

[0101] Furthermore, the monovalent organic cation includes MA. + FA + Cs + and K + At least one of them.

[0102] It should be noted that MA + It is a methylammonium ion with the chemical formula CH3NH3. + ;FA + It is a formamidinium ion, with the chemical formula H₂NCHNH₃. + .

[0103] Preferably, the divalent metal ion includes Pb. 2+ and / or Sn 2+ .

[0104] Preferably, the halide ion includes Cl. - ,Br - and I - At least one of them.

[0105] Furthermore, the thickness of the electron transport layer 200 is 10-200 nm.

[0106] Preferably, the thickness of the perovskite light-absorbing layer 300 is 100-1000 nm.

[0107] Preferably, the thickness of the molecular modification layer 400 is 1-50 nm.

[0108] Preferably, the hole transport layer 500 has a thickness of 50-300 nm.

[0109] Preferably, the thickness of the metal electrode 600 is 80-200 nm.

[0110] The second aspect of this utility model provides a method for preparing the perovskite solar cell, which involves sequentially preparing an electron transport layer 200, a perovskite light-absorbing layer 300, a molecular modification layer 400, a hole transport layer 500, and a metal electrode 600 on a conductive glass substrate 100 to obtain a perovskite solar cell.

[0111] The molecular modification layer 400 is prepared by: first coating a benzyltriethylammonium halide solution onto the perovskite light-absorbing layer 300, followed by a first heat treatment to obtain the molecular modification layer 400.

[0112] Further, the concentration of the benzyltriethylammonium halide solution is 0.1–10 mg / mL, preferably 0.5–5 mg / mL.

[0113] Typically, but not limitingly, the concentration of the benzyltriethylammonium halide solution can be, for example, 0.1 mg / mL, 0.5 mg / mL, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL, or 10 mg / mL, or any value within the range of 0.1 to 10 mg / mL. Preferred concentration ranges can be, for example, 0.5 mg / mL, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, or 5 mg / mL, or any value within the range of 0.5 to 5 mg / mL.

[0114] Preferably, the solvent in the benzyltriethylammonium halide solution includes at least one of acetonitrile, isopropanol, methanol, ethanol, dimethoxyethanol, and chloroform.

[0115] Preferably, the temperature of the first heat treatment is 100-150°C and the time is 2-60 min.

[0116] Typically, but not limitingly, the temperature of the first heat treatment can be, for example, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C, or any value within the range of 100°C to 150°C; the heat treatment time can be, for example, 2 min, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min, or 60 min, or any value within the range of 2 to 60 min.

[0117] Preferably, the first coating method is spin coating.

[0118] Preferably, the spin coating speed is 3000-6000 rpm and the time is 20-60 s.

[0119] Typically, but not limitingly, the spin coating speed can be, for example, 3000 rpm, 3500 rpm, 4000 rpm, 4500 rpm, 5000 rpm, 5500 rpm, or 6000 rpm, or any value within the range of 3000 to 6000 rpm; the spin coating time can be, for example, 20 s, 25 s, 30 s, 35 s, 40 s, 45 s, 50 s, 55 s, or 60 s, or any value within the range of 20 to 60 s.

[0120] Furthermore, the perovskite light-absorbing layer 300 is prepared by: coating a perovskite precursor solution onto the electron transport layer 200 via a second coating, followed by a second heat treatment to obtain the perovskite light-absorbing layer 300.

[0121] Preferably, the solvent in the perovskite precursor solution includes at least one of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, γ-butyrolactone, and 2-mercaptoethanol.

[0122] Preferably, the concentration of the perovskite precursor solution is 1.0 to 1.7 M.

[0123] Preferably, the temperature of the second heat treatment is 100-150°C and the time is 10-60 min.

[0124] Typically, but not limitingly, the temperature of the second heat treatment can be, for example, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C, or any value within the range of 100°C to 150°C; the heat treatment time can be, for example, 10 min, 20 min, 30 min, 40 min, 50 min, or 60 min, or any value within the range of 10 to 60 min.

[0125] Preferably, the second coating includes spin coating.

[0126] Preferably, the spin coating speed is 3000-6000 rpm and the time is 20-60 s.

[0127] Typically, but not limitingly, the spin coating speed can be, for example, 3000 rpm, 3500 rpm, 4000 rpm, 4500 rpm, 5000 rpm, 5500 rpm, or 6000 rpm, or any value within the range of 3000 to 6000 rpm; the spin coating time can be, for example, 20 s, 25 s, 30 s, 35 s, 40 s, 45 s, 50 s, 55 s, or 60 s, or any value within the range of 20 to 60 s.

[0128] Preferably, the thickness of the perovskite light-absorbing layer is 100–1000 nm.

[0129] Typically, but not limitingly, the thickness of the perovskite light-absorbing layer can be, for example, 100 nm, 200 nm, 300 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 900 nm or 1000 nm, or any value in the range of 100 nm to 1000 nm.

[0130] The fourth aspect of this utility model provides a method for preparing the perovskite composite light-absorbing layer 700 as follows: an electron transport layer 200, a perovskite composite light-absorbing layer 700, a hole transport layer 500 and a metal electrode 600 are sequentially prepared on a conductive glass substrate 100 to obtain a perovskite solar cell.

[0131] The perovskite composite light-absorbing layer 700 is prepared by adding benzyltriethylammonium halide to a perovskite precursor solution and mixing them evenly to obtain a perovskite composite solution; coating the perovskite composite solution onto the electron transport layer 200 in a third manner, and then performing a third heat treatment to obtain the perovskite composite light-absorbing layer 700.

[0132] Incorporating benzyltriethylammonium halide into the perovskite precursor solution allows it to react with residual lead iodide, forming a one-dimensional structure in situ at the grain boundaries of the perovskite film and reducing grain boundary defects.

[0133] When preparing the perovskite composite solution, the stirring temperature is 25–100℃, and the stirring time is 0.5–5 h. Benzyltriethylammonium halide can be added using a benzyltriethylammonium halide solution. The solvent used in the benzyltriethylammonium halide solution here is dimethyl sulfoxide to ensure compatibility with the perovskite precursor solution system.

[0134] Typically, but not limitingly, the stirring temperature can be, for example, 25°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, or 100°C, or any value within the range of 25°C to 100°C; the stirring time can be, for example, 0.5h, 1h, 2h, 3h, 4h, or 5h, or any value within the range of 0.5h to 5h.

[0135] Furthermore, in the perovskite composite solution, the concentration of the benzyltriethylammonium halide solution is 0.1–10 mg / mL, preferably 0.2–5 mg / mL.

[0136] Typically, but not limitingly, in the perovskite composite solution, the concentration of the benzyltriethylammonium halide solution can be, for example, 0.1 mg / mL, 0.5 mg / mL, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL, or 10 mg / mL, or any value within the range of 0.1 to 10 mg / mL. A preferred concentration range is, for example, 0.2 mg / mL, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, or 5 mg / mL, or any value within the range of 0.2 to 5 mg / mL.

[0137] Furthermore, the concentration of the perovskite precursor solution is 1.0–1.7 M.

[0138] Typically, but not limitingly, the concentration of the perovskite precursor solution can be, for example, 1.0 M, 1.1 M, 1.2 M, 1.3 M, 1.4 M, 1.5 M, 1.6 M, or 1.7 M, or any value in the range of 1.0 to 1.7 M.

[0139] During the preparation process, the perovskite precursor is dissolved in a solvent in an anhydrous and oxygen-free environment and heated and stirred at 25–100°C for 1–12 h to form a perovskite precursor solution with a concentration of 1.0–1.7 M.

[0140] Preferably, the solvent in the perovskite precursor solution includes at least one of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, γ-butyrolactone, and 2-mercaptoethanol.

[0141] Preferably, the temperature of the third heat treatment is 100-150°C and the time is 10-60 min.

[0142] Typically, but not limitingly, the temperature of the third heat treatment can be, for example, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C, or any value within the range of 100°C to 150°C; the time of the third heat treatment can be, for example, 10 min, 20 min, 30 min, 40 min, 50 min, or 60 min, or any value within the range of 10 to 60 min.

[0143] Preferably, the third coating includes spin coating.

[0144] Preferably, the spin coating speed is 3000-6000 rpm and the time is 20-60 s.

[0145] Typically, but not limitingly, the spin coating speed can be, for example, 3000 rpm, 3500 rpm, 4000 rpm, 4500 rpm, 5000 rpm, 5500 rpm, or 6000 rpm, or any value within the range of 3000 to 6000 rpm; the spin coating time can be, for example, 20 s, 25 s, 30 s, 35 s, 40 s, 45 s, 50 s, 55 s, or 60 s, or any value within the range of 20 to 60 s.

[0146] Preferably, the thickness of the perovskite composite light-absorbing layer is 100–1000 nm.

[0147] Typically, but not limitingly, the thickness of the perovskite light-absorbing layer can be, for example, 100 nm, 200 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 900 nm or 1000 nm, or any value in the range of 100 nm to 1000 nm.

[0148] The preparation method provided by this invention, whether preparing the perovskite light-absorbing layer 300 and molecular modification layer 400 separately, or directly preparing the perovskite composite light-absorbing layer 700, all employ a solution coating process. This method is highly compatible with existing perovskite solar cell fabrication technologies and can be directly integrated into existing perovskite device production lines without complex equipment modifications. The heat treatment process avoids the risk of damage to the perovskite lattice structure caused by high-temperature annealing. Simultaneously, the directional self-assembly behavior of benzyltriethylammonium halide molecules during heat treatment achieves in-situ transformation from disordered adsorption to an ordered one-dimensional structure. Furthermore, the coating process has a wide process window, which is beneficial for improving process stability and yield in large-scale production, providing technical feasibility for low-cost continuous production of perovskite modules.

[0149] Furthermore, the electron transport layer 200 is made of TiO2 or SnO2.

[0150] In some embodiments of this utility model, the method for preparing TiO2 as the electron transport layer 200 material is CBD chemical bath deposition, with a hydrothermal temperature of 50-90℃ and an annealing temperature of 90-150℃.

[0151] SnO2 is used as the material for electron transport layer 200, which is prepared by spin-coating a SnO2 solution. The spin-coating speed is 1000–4000 rpm; the annealing temperature is 80–150℃.

[0152] Typically, but not limitingly, the spin coating speed can be, for example, 1000 rpm, 1500 rpm, 2000 rpm, 2500 rpm, 3000 rpm, 3500 rpm or 4000 rpm, or any value in the range of 1000 to 4000 rpm.

[0153] The annealing temperature can be, for example, 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃ or 150℃, or any value within the range of 80℃ to 150℃.

[0154] The present invention will be further illustrated below with specific embodiments and comparative examples. However, it should be understood that these embodiments are merely for the purpose of more detailed illustration and should not be construed as limiting the present invention in any way. Unless otherwise specified, the raw materials used in the embodiments and comparative examples of the present invention are produced under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0155] Example 1

[0156] This embodiment provides a perovskite solar cell, the structural schematic of which is shown below. Figure 1 As shown, it includes a conductive glass substrate 100, and an electron transport layer 200, a perovskite light-absorbing layer 300, a molecular modification layer 400, a hole transport layer 500 and a metal electrode 600 sequentially stacked on the conductive glass substrate 100.

[0157] The molecular modification layer 400 includes a benzyltriethylammonium one-dimensional lead halide structure.

[0158] The electron transport layer 200 has a thickness of 100 nm; the perovskite light-absorbing layer 300 has a thickness of 500 nm; the molecular modification layer 400 has a thickness of 20 nm; the hole transport layer 500 has a thickness of 170 nm; and the metal electrode 600 has a thickness of 100 nm.

[0159] Example 2

[0160] This embodiment provides a perovskite solar cell, the structural schematic of which is shown below. Figure 2 As shown, it includes a conductive glass substrate 100, and a hole transport layer 500, a perovskite light-absorbing layer 300, a molecular modification layer 400, an electron transport layer 200 and a metal electrode 600 sequentially stacked on the conductive glass substrate 100.

[0161] The molecular modification layer 400 includes a benzyltriethylammonium one-dimensional lead halide structure.

[0162] The hole transport layer 500 has a thickness of 170 nm; the perovskite light-absorbing layer 300 has a thickness of 500 nm; the molecular modification layer 400 has a thickness of 20 nm; the electron transport layer 200 has a thickness of 100 nm; and the metal electrode 600 has a thickness of 100 nm.

[0163] Example 3

[0164] This embodiment provides a perovskite solar cell, the structural schematic of which is shown below. Figure 3 As shown, it includes a conductive glass substrate 100, and an electron transport layer 200, a perovskite composite light-absorbing layer 700, a hole transport layer 500, and a metal electrode 600 sequentially stacked on the conductive glass substrate 100.

[0165] The perovskite composite light-absorbing layer 700 includes a one-dimensional lead halide structure of perovskite and benzyltriethylammonium.

[0166] The electron transport layer 200 has a thickness of 100 nm; the perovskite composite light-absorbing layer 700 has a thickness of 500 nm; the hole transport layer 500 has a thickness of 170 nm; and the metal electrode 600 has a thickness of 100 nm.

[0167] Example 4

[0168] This embodiment provides a perovskite solar cell, the structural schematic of which is shown below. Figure 4 As shown, it includes a conductive glass substrate 100, and a hole transport layer 500, a perovskite composite light-absorbing layer 700, an electron transport layer 200 and a metal electrode 600 sequentially stacked on the conductive glass substrate 100.

[0169] The perovskite composite light-absorbing layer 700 includes a one-dimensional lead halide structure of perovskite and benzyltriethylammonium.

[0170] The hole transport layer 500 has a thickness of 170 nm; the perovskite composite light-absorbing layer 700 has a thickness of 500 nm; the electron transport layer 200 has a thickness of 100 nm; and the metal electrode 600 has a thickness of 100 nm.

[0171] Example 5

[0172] This embodiment provides a method for fabricating the perovskite solar cell of Example 1, the specific process of which is as follows:

[0173] 1. Cleaning of conductive glass substrate: The purchased FTO glass is ultrasonically cleaned with deionized water, acetone and anhydrous ethanol in sequence for 30 minutes. The glass surface is then dried with nitrogen gas and set aside for use.

[0174] 2. Preparation of electron transport layer 200: After immersing the FTO glass in ultraviolet ozone for 15 minutes, 850 μL of TiCl4 solution was slowly added dropwise to a glass vial containing 40 mL of ultrapure water (the vial was pre-frozen). After the ice completely melted, the mixture was transferred to a petri dish. The petri dish was placed in a 70℃ oven for hydrothermal treatment for 50 min. After the reaction was complete, the residual TiCl4 on the substrate surface was washed with ultrapure water, and then annealed in a 150℃ oven for 1 h to finally obtain the TiO2 film.

[0175] 3. Preparation of perovskite light-absorbing layer 300: In an anhydrous and oxygen-free environment, CsI, MABr, FAI, PbI2, and MACl were dissolved in a mixed solvent of N,N-dimethylformamide and dimethyl sulfoxide with a volume ratio of 4:1 in a molar ratio of 0.05:0.09:0.85:0.955:0.02. The solution was stirred at 55°C for 2 hours. After filtration through an organic filter, a 1.55 M perovskite precursor solution was obtained. 0.05 FA 0.85 MA 0.1 Pb(I 0.97 Br 0.03 3. Take 25 μL of perovskite precursor solution and drop it onto a conductive glass substrate 100 coated with electron transport layer 200. Spin coat at 4000 rpm for 30 s. Add 200 μL of ethyl acetate in the last 10 s before spin coat. After spin coat, anneal at 130 °C for 10 min to obtain perovskite light-absorbing layer 300.

[0176] 4. Preparation of molecular modification layer 400: In an anhydrous and oxygen-free environment, benzyltriethylammonium iodide molecules were dissolved in isopropanol solvent at room temperature with stirring to obtain a solution with a concentration of 1.5 mg / mL. 40 μL of the benzyltriethylammonium iodide solution was dropped onto the perovskite light-absorbing layer 300. The spin-coating speed was 4000 rpm, and the spin-coating time was 30 s. After spin-coating, the layer was heat-treated at 100℃ for 2 min to obtain molecular modification layer 400.

[0177] 5. Preparation of hole transport layer 500: After thoroughly mixing the chlorobenzene solution of hole transport material Spiro-OMeTAD, take 25 μL and drop it onto the molecular modification layer 400. The spin coating speed is 4000 rpm and the spin coating time is 30 s to obtain hole transport layer 500.

[0178] 6. Preparation of a 600-layer metal electrode: Using thermal evaporation, 80 nm of silver is deposited on top of the hole transport layer 500.

[0179] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 24.11%. Figure 5This is a current-voltage curve of the perovskite solar cell prepared in Example 5. Figure 6 As shown, Example 5 exhibits better stability compared to Comparative Example 1.

[0180] Example 6

[0181] This embodiment provides another method for preparing the perovskite solar cell of Example 1. The difference from Example 5 is that the concentration of benzyltriethylammonium iodide solution in step 3 is 0.5 mg / mL. The other raw materials and preparation steps are the same as in Example 5, and will not be repeated here.

[0182] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.73%. Figure 7 The image shows the current-voltage curve of the perovskite solar cell prepared in Example 6.

[0183] Example 7

[0184] This embodiment provides another method for preparing the perovskite solar cell of Example 1. The difference from Example 5 is that the concentration of benzyltriethylammonium iodide solution in step 3 is 3 mg / mL. The other raw materials and preparation steps are the same as in Example 5, and will not be repeated here.

[0185] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.23%. Figure 8 The image shows the current-voltage curve of the perovskite solar cell prepared in Example 7.

[0186] Example 8

[0187] This embodiment provides another method for preparing the perovskite solar cell of Example 1. The difference from Example 5 is that benzyltriethylammonium chloride is used instead of benzyltriethylammonium iodide in step 3. The remaining raw materials and preparation steps are the same as in Example 5, and will not be repeated here.

[0188] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.76%. Figure 9 The image shows the current-voltage curve of the perovskite solar cell prepared in Example 8.

[0189] Example 9

[0190] This embodiment provides another method for preparing the perovskite solar cell of Example 1. The difference from Example 5 is that benzyltriethylammonium bromide is used instead of benzyltriethylammonium iodide in step 3. The remaining raw materials and preparation steps are the same as in Example 5, and will not be repeated here.

[0191] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.54%. Figure 10 The current-voltage curve is shown for the perovskite solar cell prepared in Example 9.

[0192] Example 10

[0193] This embodiment provides a method for fabricating the perovskite solar cell of Example 3, the specific process of which is as follows:

[0194] 1-2: Same as the corresponding steps in Example 5.

[0195] 3. Preparation of perovskite composite light-absorbing layer 700: In an anhydrous and oxygen-free environment, benzyltriethylammonium iodide molecules were dissolved in dimethyl sulfoxide solvent at room temperature by stirring to obtain a benzyltriethylammonium iodide solution with a concentration of 0.5 mg / mL.

[0196] In an anhydrous and oxygen-free environment, CsI, MABr, FAI, PbI2, and MACl were dissolved in a mixed solvent of N,N-dimethylformamide and dimethyl sulfoxide in a molar ratio of 0.05:0.09:0.85:0.955:0.02 (4:1 volume ratio). 10 μL of benzyltriethylammonium iodide solution was added, and the mixture was stirred at 55 °C for 2 h. After filtration through an organic filter, a 1.55 M perovskite composite solution was obtained, wherein the molecular formula of the perovskite is CsI. 0.05 FA 0.85 MA 0.1 Pb(I 0.97 Br 0.03 3.

[0197] 25 μL of perovskite composite solution was dropped onto a conductive glass substrate 100 coated with electron transport layer 200. The spin coating speed was 4000 rpm and the spin coating time was 30 s. In the last 10 s before the end of the spin coating, 200 μL of ethyl acetate was dropped. After the spin coating was completed, the substrate was heat-treated at 130 °C for 10 min to obtain perovskite composite light-absorbing layer 700.

[0198] 4-6: Same as the corresponding steps in Example 5.

[0199] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.99%. Figure 11 The current-voltage curve is shown for the perovskite solar cell prepared in Example 10.

[0200] Example 11

[0201] This embodiment provides another method for preparing the perovskite solar cell of Example 3. The difference from Example 10 is that the concentration of the benzyltriethylammonium iodide solution used in step 3 is 1.0 mg / mL. The other raw materials and preparation steps are the same as in Example 10, and will not be repeated here.

[0202] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.21%. Figure 12 The current-voltage curve is shown for the perovskite solar cell prepared in Example 11.

[0203] Example 12

[0204] This embodiment provides another method for preparing the perovskite solar cell of Example 3. The difference from Example 10 is that benzyltriethylammonium chloride is used instead of benzyltriethylammonium iodide in step 3. The other raw materials and preparation steps are the same as in Example 10, and will not be repeated here.

[0205] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.34%. Figure 13 The current-voltage curve is shown for the perovskite solar cell prepared in Example 12.

[0206] Example 13

[0207] This embodiment provides another method for preparing the perovskite solar cell of Example 3. The difference from Example 10 is that benzyltriethylammonium bromide is used instead of benzyltriethylammonium iodide in step 3. The other raw materials and preparation steps are the same as in Example 10, and will not be repeated here.

[0208] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 23.33%. Figure 14 The current-voltage curve is shown for the perovskite solar cell prepared in Example 13.

[0209] Comparative Example 1

[0210] This comparative example provides a perovskite solar cell, such as Figure 15 As shown, its structure differs from that of Example 1 in that it does not have the molecular modification layer 400, while the thickness of the other structural layers is the same as that of Example 1, and will not be described again here.

[0211] The preparation method of this perovskite solar cell differs from that of Example 5 in that step 4 is omitted. The rest of the preparation method is the same as that of Example 5, and will not be repeated here.

[0212] The prepared perovskite solar cell was tested for performance, and its photoelectric conversion efficiency was 22.01%. Figure 16 The current-voltage curve of the perovskite solar cell prepared in Comparative Example 1 is shown.

[0213] Characterization Example 1

[0214] The perovskite composite light-absorbing layer prepared in Example 10 was subjected to scanning electron microscopy, and the resulting image is shown below. Figure 17 As shown, from Figure 17 It can be seen that the island-like structure on the surface is a one-dimensional lead halide structure of benzyltriethylammonium.

[0215] The perovskite light-absorbing layer obtained in Comparative Example 1 was subjected to scanning electron microscopy, and the resulting image is shown below. Figure 18 As shown, from Figure 18 It can be seen that the perovskite film is flat and dense.

[0216] Characterization Example 2

[0217] from Figure 19 It can be seen that the single crystal structure of the benzyltriethylammonium one-dimensional lead halide structure is composed of benzyltriethylammonium ions and one-dimensional lead iodine chains. The X-ray powder diffraction pattern shows the successful modification of the benzyltriethylammonium one-dimensional lead halide structure on the perovskite film.

[0218] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A perovskite solar cell, characterized by, It includes a layered conductive glass substrate, an electron transport layer, a perovskite light-absorbing layer, a molecular modification layer, a hole transport layer, and a metal electrode; The molecular modification layer includes a benzyltriethylammonium one-dimensional lead halide structure.

2. The perovskite solar cell according to claim 1, characterized in that, It includes a conductive glass substrate, and an electron transport layer, a perovskite light-absorbing layer, a molecular modification layer, a hole transport layer, and a metal electrode sequentially stacked on the conductive glass substrate. 3.The perovskite solar cell of claim 1, wherein, It includes a conductive glass substrate, and a hole transport layer, a perovskite light-absorbing layer, a molecular modification layer, an electron transport layer, and a metal electrode sequentially stacked on the conductive glass substrate.

4. The perovskite solar cell according to any one of claims 1 to 3, characterized in that, The one-dimensional lead halide structure of benzyltriethylammonium is formed by benzyltriethylammonium halide.

5. The perovskite solar cell according to any one of claims 1 to 3, characterized in that, The conductive glass substrate is FTO; The electron transport layer is made of TiO2 or SnO2; The hole transport layer is made of Spiro-OMeTAD material; The metal electrode is made of Ag or Au.

6. The perovskite solar cell according to any one of claims 1 to 3, characterized in that, The thickness of the electron transport layer is 10-200 nm; The thickness of the perovskite light-absorbing layer is 100-1000 nm; The thickness of the molecular modification layer is 1-50 nm; The thickness of the hole transport layer is 50-300 nm; The thickness of the metal electrode is 80-200 nm.

7. A perovskite solar cell, characterized in that, The perovskite light-absorbing layer and the molecular modification layer in the perovskite solar cell according to any one of claims 1 to 6 are replaced by a perovskite composite light-absorbing layer. The perovskite composite light-absorbing layer includes a one-dimensional lead halide structure of perovskite and benzyltriethylammonium.

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