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CN-116487477-B - N-P homojunction all-inorganic perovskite solar cell and preparation method thereof

CN116487477BCN 116487477 BCN116487477 BCN 116487477BCN-116487477-B

Abstract

The invention discloses an N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics. The invention can be used for breaking through the indoor photovoltaic efficiency limit, and the CsPbI 3 perovskite film with N-P homojunction is prepared in a glove box by treating the interface of the all-inorganic perovskite (CsPbI 3 ) film with a surface modification material (sodium dodecyl sulfate: SDS). The formation of surface PbS was observed with a Scanning Electron Microscope (SEM), and the generation of N-P homojunction was examined with an electrostatic potential atomic force microscope (KPFM). An N-P homojunction is formed on the surface of the CsPbI 3 film, so that the problem of energy band matching of the CsPbI 3 perovskite film and the charge transport layer is solved. Most importantly, J sc is greatly improved, which provides an effective strategy for improving J sc of the indoor photovoltaic enhancement of all-inorganic perovskite.

Inventors

  • GONG XIU
  • YANG QU
  • QI XIAOSI
  • ZHANG HAOZHE
  • DING JUNFEI
  • YANG JINGLIANG

Assignees

  • 贵州大学

Dates

Publication Date
20260505
Application Date
20230418

Claims (7)

  1. 1. The preparation method of the N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaic is characterized by comprising the following steps of: 1. Cleaning and treating a solar cell substrate, namely sequentially ultrasonically cleaning a glass substrate through a detergent, deionized water, acetone and ethanol, drying the cleaned glass substrate, and treating the dried glass substrate by an ultraviolet plasma cleaner to obtain a sample ①; 2. Heating a sample ① to 70 ℃, spin-coating TiO 2 on the surface of the sample ① by using a spin coater to serve as an electron transport layer of a solar cell, and annealing to obtain a sample ②; 3. In a glove box filled with argon, chemometrics CsI, pbI 2 and DMAI are dissolved in DMF and DMSO solvent in a molar ratio of 1:1:1, stirred to prepare CsPbI 3 perovskite solution, and filtered to obtain CsPbI 3 solution; 4. the proportion of the modified material solution is that sodium dodecyl sulfate SDS is stirred and dissolved in chlorobenzene in a glove box filled with argon, and filtered to obtain SDS solution; 5. The preparation of the N-P homojunction perovskite film comprises the steps of transferring a sample ② into a glove box filled with argon through vacuumizing, preparing an N-P homojunction CsPbI 3 film on a spin coater, rapidly dripping an SDS solution in the middle of spin coating the CsPbI 3 film, and finally annealing to obtain a sample ③; 6. Preparing a hole transport layer, namely spin-coating a Spiro-OMeTAD solution on a sample ③ to obtain a sample ④; 7. And (3) electrode evaporation, namely selecting an evaporation Ag electrode as a battery anode, transferring a sample ④ to a rotary evaporator for evaporation, and obtaining the complete perovskite solar cell device.
  2. 2. The method for preparing the N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics according to claim 1 is characterized in that in the first step, the glass substrate is an ITO conductive glass substrate, the ultrasonic cleaning time is 10-15 min, the drying temperature of an oven is 60-80 ℃ and the time is 4-5 h, and the power of an ultraviolet plasma cleaning machine is 60W and the time is 60 s.
  3. 3. The method for preparing the N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics according to claim 1, wherein in the second step, the rotation speed of the electron transport layer TiO 2 is controlled to be 5000 rpm/min on a spin coater, the time is 30 s, the humidity in a fume hood is 20% RH, and the annealing condition is annealing for 1 hour at 450 ℃.
  4. 4. The preparation method of the N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics, which is disclosed in claim 1, is characterized in that in the third step, perovskite is dissolved in a mixed solution with the volume ratio of DMF to DMSO being 4:1, the stirring time of a magnetic stirrer is 5h, and an organic filter head with the thickness of 0.45 μm is adopted for filtering.
  5. 5. The preparation method of the N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics, which is disclosed in claim 1, is characterized in that in the fourth step, the concentration of SDS solution is 9 mmol/mL, and the stirring time of a magnetic stirrer is 5 h.
  6. 6. The preparation method of the N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics, which is disclosed in claim 1, is characterized in that in the fifth step, the surface spin coating is performed by adopting 50 uL CsPbI 3 solution for standing spin coating, the spin coating rotating speed is 3000 rpm/min, the spin coating time is 30 s, the middle spin coating means that SDS solution is dripped when 15 s is adopted, the annealing temperature is 180 ℃, and the annealing time is 3 min.
  7. 7. The preparation method of the N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics, which is disclosed in claim 1, is characterized in that in the step seven, the evaporation condition of a rotary evaporator is that the vacuum degree is not less than 1X 10 -4 Pa, and the thickness of evaporation is 80 nm.

Description

N-P homojunction all-inorganic perovskite solar cell and preparation method thereof Technical Field The invention mainly relates to the technical field of indoor photovoltaics of solar cells, in particular to an N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaics. Background The rapid development of internet of things (IoT) technology has led to the popularity of a large number of low power electronic devices. However, low power electronic products require a continuous power supply. Indoor light energy is considered as low intensity light that utilizes unique Indoor Photovoltaics (IPVs) to provide continuous power to internet of things electronic devices. The spectral range of the indoor light source is in the visible range (between 400-800 nm), so the spectral range determines the ideal bandgap range of the IPV to be 1.7-1.9 eV. However, low intensity indoor light sources result in poor performance of commercial photovoltaic devices such as crystalline silicon (c-Si). Surprisingly, perovskite Solar Cells (PSCs) exhibit higher efficiency at low intensity indoor light sources. In a large number of studies, power Conversion Efficiencies (PCEs) of over 40% have been reported in the laboratory despite the organic-inorganic halide lead perovskite band gap mismatch (≡1.60 eV). However, experiments have shown that the short circuit current density (J sc) of most narrow bandgap Perovskite IPVs (PIPVs) has reached a limit and that an increase in open circuit voltage (V oc) is highly desirable. In more and more researches, methods such as passivation defect and the like are beneficial to the device to work under indoor light source, but V oc caused by narrow band gap is still low. Thus, while maintaining a narrow bandgap J sc, the wide bandgap facilitates an increase in V oc, and a higher PCE is expected. Since the wide bandgap (1.70 eV) organic-inorganic hybrid perovskite (OIHPs) typically has shorter diffusion length, the optical phase segregation is more severe, resulting in greater V oc losses. An all-inorganic perovskite (such as CsPbI 3) is one of the most suitable answers to this problem because of its tunable band gap (1.7-2.3 eV). In recent years, the PCE of all-inorganic CsPbI 3 Perovskite Solar Cells (PSCs) has also rapidly increased, with our group of PCEs reaching 19.17%. While the black phase CsPbI 3 perovskite phase has relatively poor stability and is easily converted into a thermodynamically stable yellow phase (e.g., delta-CsPbI 3). To improve the J sc and hydrophobicity of CsPbI 3 PSCs, a number of process strategies are used to optimize CsPbI 3 films, including passivation defects, strain engineering, and manipulation of crystallinity. Such as Du and the like, effectively reduces defects by adding a new ionic liquid to passivate iodine vacancies in the CsPbI 3 film. Ke et al apply pressure in the CsPbI 3 film, and control the octahedral tilt of [ PbI 6]4- by adjusting the pressure, thereby stabilizing the cubic CsPbI 3 structure. Xu et al effectively reduced the loss of V oc by modifying the buried interface to adjust the crystal quality of CsPbI 3. indeed, these strategies effectively increase the hydrophobicity of CsPbI 3 and PCE. However, the energy band matching problem of the CsPbI 3 perovskite thin film with the charge transport layer is ignored. In recent years, many studies have shown that the surface type (p-type or n-type) of perovskite films can be changed by doping perovskite. Xiong et al utilized capsaicin to convert the MAPbI 3 surface from p-type to n-type, enhancing charge transfer and reducing non-radiative losses. Therefore, the all-inorganic IPVs has important significance in constructing CsPbI 3 N-P homojunction through doping, improving energy level matching, enhancing internal electric field and enhancing J sc. Disclosure of Invention According to the invention, an interface modification strategy is adopted, and Sodium Dodecyl Sulfate (SDS) is introduced into a perovskite layer to prepare the efficient and stable PSCs. The results show that the hydrophobicity of long-chain SDS improves the surface moisture resistance of the CsPbI 3 film. The non-coordinated Pb 2+ in CsPbI 3 interacts with the sulfuric acid functional group to generate PbS in situ on the perovskite surface. The unique hole transport properties of PbS increase the surface potential of the perovskite, resulting in spontaneous formation of N-P homojunctions in CsPbI 3, further speeding up the hole transport efficiency of CsPbI 3. Pb 2+ forms a strong bond with the sulfuric acid functional group at the perovskite interface, and the long chain structure greatly inhibits the degradation of CsPbI 3. This work provides a viable solution for breaking through IPVs PSCs efficiency bottlenecks. The invention provides an N-P homojunction all-inorganic perovskite solar cell applied to indoor photovoltaic, and provides a feasible solution for breaking through IPVs PSCs efficiency bott