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CN-116234332-B - Perovskite solar cell based on ammonium iodide modified double-layer electron transport layer and acetone doped lead iodide precursor and preparation method thereof

CN116234332BCN 116234332 BCN116234332 BCN 116234332BCN-116234332-B

Abstract

A perovskite solar cell based on an ammonium iodide modified double-layer SnO 2 electron transport layer and an acetone doped lead iodide precursor and a preparation method thereof belong to the technical field of perovskite solar cells. The composite material consists of an ITO conductive glass substrate, an ammonium iodide modified double-layer SnO 2 electron transport layer, an acetone doped lead iodide precursor perovskite active layer, a phenethyl ammonium iodide surface passivation layer, a spira-OMeTAD hole transport layer and a silver electrode in sequence. According to the invention, the double-layer SnO 2 electron transport layer is modified by ammonium iodide, so that the extraction and the transmission of electrons are promoted, the hysteresis phenomenon caused by the accumulation of charges at an interface is inhibited, and the conductivity is enhanced. In addition, acetone with low dielectric constant is doped in the lead iodide precursor solution, so that abundant holes appear in the lead iodide film, the defect density of a perovskite layer is reduced, a high-quality film is formed, stable and good carrier transmission is realized, and the performance of the perovskite solar cell is further improved.

Inventors

  • GUO WENBIN
  • ZHANG QIANG
  • LIU CHUNYU
  • Ren guanhua
  • HAN WENBIN
  • LI ZHUOWEI
  • DENG YANYU

Assignees

  • 吉林大学

Dates

Publication Date
20260508
Application Date
20230207

Claims (7)

  1. 1. The preparation method of the perovskite solar cell based on the ammonium iodide double-layer electron transport layer and the acetone doped lead iodide precursor comprises the following steps: 1) Cleaning process for substrates Ultrasonically cleaning an ITO conductive glass substrate by using acetone, ethanol and deionized water for 10-20 min respectively, and then drying by using nitrogen; 2) Preparation of SnO 2 electron transport layer Adding deionized water into a SnO 2 aqueous dispersion with the mass concentration of 15% according to the volume ratio of 1:3-8 to obtain diluted SnO 2 aqueous dispersion, spin-coating the diluted SnO 2 aqueous dispersion on a cleaned ITO conductive glass substrate, and annealing for 10-30 min at 140-180 ℃ to obtain a SnO 2 electron transport layer on the ITO conductive glass substrate; Dissolving ammonium iodide in the diluted SnO 2 aqueous dispersion to prepare an ammonium iodide solution with the ammonium iodide concentration of 0.5-2 mg/mL, spin-coating the ammonium iodide solution on the SnO 2 electron transport layer, and annealing for 10-30 min at 140-180 ℃ to obtain an ammonium iodide modified SnO 2 electron transport layer, wherein the SnO 2 electron transport layer and the ammonium iodide modified SnO 2 electron transport layer are called an ammonium iodide modified double-layer SnO 2 electron transport layer; 3) Preparation of perovskite active layer Preparation of a solution of the active layer Dissolving 645.4-737.6 mg of lead iodide in a mixed solvent with the volume ratio of N, N-dimethylformamide to dimethyl sulfoxide being 9:1, doping 1-20 mu L of acetone in the mixed solvent, and stirring at 500-700 rpm for 15-20 hours to obtain a lead iodide solution, dissolving 90mg of formamidine hydroiodinate, 6.39mg of methyl ammonium iodide and 9mg of methyl ammonium chloride in 1mL of isopropanol, and stirring at 500-700 rpm for 15-20 hours to obtain an organic mixture solution; b preparation of perovskite active layer Spin-coating a lead iodide solution on an ammonium iodide modified double-layer SnO 2 electron transport layer, and annealing for 1-3 min at 65-75 ℃ to obtain a lead iodide film, spin-coating 60-120 mu L of an organic mixture solution on the lead iodide film, and annealing for 20-40min at 140-180 ℃ to obtain a perovskite active layer; 4) Preparation of phenethyl ammonium iodide surface passivation layer Dissolving 2-4 mg of phenethyl ammonium iodide in 1mL of isopropanol, and stirring at 500-700 rpm for 15-20 hours to obtain phenethyl ammonium iodide solution; 5) Preparation of a spiro-OMeTAD hole transport layer Preparation of a hole transport layer solution Dissolving 72.3mg of spiro-OMeTAD in 1mL of chlorobenzene, stirring for 1-2 h at 500-700 rpm to obtain a spiro-OMeTAD original solution, dissolving 520mg of LiTFSI in 1mL of acetonitrile, stirring for 1-2 h at 500-700 rpm to obtain a LiTFSI acetonitrile solution, adding 17.6 mu L of LiTFSI acetonitrile solution and 28.5 mu L of 4-tert-butylpyridine solution into the spiro-OMeTAD original solution, and stirring for 10-15 h at 500-700 rpm to obtain a hole transport layer solution; b preparation of hole transport layer Spin-coating a hole transport layer solution on a surface passivation layer of phenethyl ammonium iodide to prepare a spira-OMeTAD hole transport layer; 6) Ag electrode preparation Evaporating Ag electrode on the spiro-OMeTAD hole transport layer under pressure of 1×10 -4 ～1×10 -3 Pa at growth rate of Thus obtaining the perovskite solar cell based on the ammonium iodide double-layer electron transport layer and the acetone doped lead iodide precursor.
  2. 2. The method for preparing the perovskite solar cell based on the ammonium iodide double-layer electron transport layer and the acetone doped lead iodide precursor, as claimed in claim 1, is characterized in that the spin coating rotating speed in the step 2) is 3000-6000 rpm, and the spin coating time is 20-40 s.
  3. 3. The method for preparing the perovskite solar cell based on the ammonium iodide double-layer electron transport layer and the acetone doped lead iodide precursor, as claimed in claim 1, is characterized in that the spin-coating speed of the lead iodide solution in the step 3) is 1800-2200 rpm, the spin-coating time is 20-30 s, the spin-coating speed of the organic mixture solution is 1800-2200 rpm, and the spin-coating time is 25-35 s.
  4. 4. The method for preparing the perovskite solar cell based on the ammonium iodide double-layer electron transport layer and the acetone doped lead iodide precursor, as claimed in claim 1, is characterized in that the spin-coating speed of the phenethyl ammonium iodide solution in the step 4) is 3000-5000 rpm, and the spin-coating time is 30-40 s.
  5. 5. The method for preparing the perovskite solar cell based on the ammonium iodide double-layer electron transport layer and the acetone doped lead iodide precursor, as claimed in claim 1, is characterized in that the spin-coating speed of the cavity transport layer solution in the step 5) is 3500-4500 rpm, and the spin-coating time is 20-30 s.
  6. 6. The preparation method of the perovskite solar cell based on the ammonium iodide double-layer electron transport layer and the acetone doped lead iodide precursor, as claimed in claim 1, is characterized in that the thickness of the SnO 2 electron transport layer is 10-20 nm, the thickness of the ammonium iodide modified SnO 2 electron transport layer is 10-20 nm, the thickness of the perovskite active layer is 0.8-1.2 mu m, the thickness of the spiro-OMeTAD hole transport layer is 200-300 nm, and the thickness of the Ag electrode is 80-100 nm.
  7. 7. A perovskite solar cell based on an ammonium iodide double-layer electron transport layer and an acetone doped lead iodide precursor is characterized by being prepared by the method of any one of claims 1-6.

Description

Perovskite solar cell based on ammonium iodide modified double-layer electron transport layer and acetone doped lead iodide precursor and preparation method thereof Technical Field The invention belongs to the technical field of perovskite solar cells, and particularly relates to a perovskite solar cell based on an ammonium iodide modified double-layer SnO 2 electron transport layer and an acetone doped lead iodide precursor and a preparation method thereof. Background The perovskite solar cell has the excellent characteristics of high absorption coefficient, high carrier mobility, long carrier life, bipolar transmission, solution-type preparation and the like, and is low in preparation cost and high in efficiency, so that the perovskite solar cell becomes a new research hot spot. Among them, solvent engineering has been widely used in improving perovskite thin film properties, and is mainly divided into one-step and two-step methods. The main process of the one-step method is to prepare a precursor solution by a lead salt precursor and an organic halide in a certain stoichiometric ratio, then spin-coat the precursor solution directly on a substrate, and then anneal the precursor solution. The perovskite layer prepared by the method has poor controllability, small grain size, incomplete coverage and a certain pinhole. However, the two-step process has better morphology controllability and crystallization reproducibility, which involves sequential deposition of the two precursors. Lead iodide is first coated onto a substrate to form a flat film and is further converted to a perovskite layer after exposure to an organic halide solution. However, in the two-step method, the morphology of the lead iodide thin film has great influence on the diffusion of organic halides into perovskite, and perovskite is often formed due to the reaction of lead iodide on the upper layer, so that the permeation and diffusion of the organic halides are hindered, the incomplete conversion of lead iodide affects the charge transmission, and the performance of the perovskite solar cell is reduced. Disclosure of Invention The invention aims to provide a perovskite solar cell based on an ammonium iodide modified double-layer SnO 2 electron transport layer and an acetone doped lead iodide precursor and a preparation method thereof. The perovskite solar cell based on the ammonium iodide modified double-layer SnO 2 electron transport layer and the acetone doped lead iodide precursor comprises an ITO conductive glass substrate, an ammonium iodide modified double-layer SnO 2 (tin dioxide, alfasin) electron transport layer, an acetone (Chinese medicine) doped lead iodide (PbI 2, sianBaolast) precursor prepared perovskite active layer, a phenethyl ammonium iodide (PEAI, sianBaolast) surface passivation layer, 2', 7 ' -tetrakis [ N, N-bis (4-methoxyphenyl) amino ] -9,9' -spirobifluorene (spiro-OMeTAD, sianBaolast) hole transport layer and a silver (Ag) electrode from bottom to top. The perovskite active layer has a thickness of 0.8-1.2 mu m, the ammonium iodide modified double-layer SnO 2 electron transport layer has a thickness of 20-40 nm, the spiro-OMeTAD hole transport layer has a thickness of 200-300 nm, the surface passivation layer of phenethyl ammonium iodide has a negligible thickness, and the Ag electrode has a thickness of 80-100 nm. The invention relates to a preparation method of perovskite solar cell based on an ammonium iodide double-layer electron transport layer and acetone doped lead iodide precursor, which comprises the following steps of 1) Cleaning process for substrates Ultrasonically cleaning an ITO conductive glass substrate by using acetone, ethanol and deionized water for 10-20 min respectively, and then drying by using nitrogen; 2) Preparation of SnO 2 electron transport layer Adding deionized water into a commercial SnO 2 aqueous dispersion with the mass concentration of 15% according to the volume ratio of 1:3-8 to obtain diluted SnO 2 aqueous dispersion, spin-coating the diluted SnO 2 aqueous dispersion on the cleaned ITO conductive glass substrate for 20-40 s at the rotating speed of 3000-6000 rpm, and annealing for 10-30 min at 140-180 ℃ to obtain a SnO 2 electron transport layer with the thickness of 10-20 nm on the ITO conductive glass substrate; Dissolving ammonium iodide in the diluted SnO 2 aqueous dispersion to prepare an ammonium iodide solution with the concentration of 0.5-2 mg/mL, spin-coating the ammonium iodide solution on the SnO 2 electron transport layer for 20-40 s at the rotating speed of 3000-6000 rpm, and annealing for 10-30 min at 140-180 ℃ to obtain an ammonium iodide modified SnO 2 electron transport layer, wherein the thickness of the ammonium iodide modified SnO 2 electron transport layer is 10-20 nm, and the SnO 2 electron transport layer and the ammonium iodide modified SnO 2 electron transport layer are laminated to form an ammonium iodide modified double-layer SnO 2 electron transport