US 12,225,743 B2
Long-acting and stable perovskite solar cell and preparation method thereof
Ligang Xu, Nanjing (CN); Wenxuan Lv, Nanjing (CN); Runfeng Chen, Nanjing (CN); and Wei Huang, Nanjing (CN)
Assigned to Nanjing University of Posts & Telecommunications, Nanjing (CN)
Filed by Nanjing University of Posts & Telecommunications, Nanjing (CN)
Filed on Aug. 29, 2024, as Appl. No. 18/818,668.
Application 18/818,668 is a continuation of application No. PCT/CN2023/135366, filed on Nov. 30, 2023.
Claims priority of application No. 202310178293.1 (CN), filed on Feb. 28, 2023.
Prior Publication US 2024/0423000 A1, Dec. 19, 2024
Int. Cl. H01L 31/044 (2014.01); H10K 30/40 (2023.01); H10K 30/88 (2023.01)
CPC H10K 30/88 (2023.02) [H10K 30/40 (2023.02)] 3 Claims
OG exemplary drawing
 
1. A perovskite solar cell, characterized in that a structure of the perovskite solar cell comprises: a substrate, an anode layer, a hole-transporting layer, a perovskite multi-protective layer, a composite electron-transporting layer, a hole blocking layer, and a metal cathode layer that are arranged sequentially from bottom to top of the structure of the perovskite solar cell;
wherein the perovskite multi-protective layer comprises: a perovskite light-absorbing layer and a multifunctional protection layer, the perovskite multi-protective layer is configured to improve a stability of the perovskite solar cell through triple protection, and the triple protection comprises: an ion exchange reaction, a hydrophobic effect and hydrogen bonding based on raw materials of the perovskite solar cell, and passivation of perovskite defects; and
wherein a preparation method of the perovskite solar cell comprises the following steps:
preparing the anode layer on the substrate by using transparent glass as the substrate, and spin-coating a poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) solution on the anode layer to obtain the hole-transporting layer;
spin-coating a perovskite precursor solution on the hole-transporting layer by using a one-step anti-solvent method;
wherein the perovskite precursor solution is prepared by dissolving formamidinium iodide (FAI), methylammonium bromide (MABr), lead(II) bromide (PbBr2), and lead(II) iodide (PbI2) in a mixed solvent of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) with a volume ratio of the DMF to the DMSO being 4:1 to obtain a first mixed solution, then dissolving cesium iodide (CsI) in DMSO to obtain a second mixed solution, and mixing the first mixed solution and the second mixed solution before spin-coating the perovskite precursor solution; and a speed of spin-coating the perovskite precursor solution is in a range of 5,000 revolutions per minute (rpm) to 10,000 rpm, and a time for spin-coating the perovskite precursor solution is 55 seconds (s);
dropwise adding an anti-solvent of ethyl acetate (EA) containing ammonium hexafluorophosphate (NH4PF6) during spin-coating the perovskite precursor solution, wherein a concentration of the NH4PF6 in the anti-solvent of EA containing NH4PF6 is 1 milligram per milliliter (mg/mL), a time for dropwise adding the anti-solvent of EA containing the NH4PF6 is 15 s before finishing spin-coating the perovskite precursor solution, and an addition amount of the anti-solvent of EA is 150 microliters (μL);
placing the hole-transporting layer coated with the perovskite precursor solution on a heating stage for an annealing reaction after finishing spin-coating the perovskite precursor solution, and obtaining the perovskite multi-protective layer after the annealing reaction is finished;
wherein a lower portion of the perovskite multi-protective layer is a perovskite crystal with a composition of (Cs0.05FA0.81MA0.14)Pb(Br0.14I0.86)3 and an upper portion of the perovskite multi-protective layer is an ion-exchanged perovskite crystal with a composition of (Cs0.05FA0.81MA0.14)Pb(Br0.14I0.86-x(PF6)x)3 that together constitute the perovskite light-absorbing layer of the perovskite multi-protective layer, and a top surface of the perovskite multi-protective layer is the multifunctional protection layer made from the NH4PF6;
spin-coating a [6,6]-phenyl C61 butyric acid methyl ester (PC61BM) solution on the multifunctional protection layer to obtain a PC61BM layer, and then depositing fullerene (C60) on the PC61BM layer to construct the composite electron-transporting layer; and
wherein a lower layer of the composite electron-transporting layer is the PC61BM layer, and an upper layer of the composite electron-transporting layer is the C60;
evaporating lithium fluoride (LiF) on the composite electron-transporting layer as the hole blocking layer, and then evaporating a metal material on the hole blocking layer to form the metal cathode layer, thereby obtaining the perovskite solar cell.