Dual Passivation of Perovskite and SnO₂ for High‐Efficiency MAPbI₃ Perovskite Solar Cells

Abstract

So far, most techniques for modifying perovskite solar cells (PSCs) focus on either the perovskite or electron transport layer (ETL). For the sake of comprehensively improving device performance, a dual‐functional method of simultaneously passivating trap defects in both the perovskite and ETL films is proposed that utilizes guidable transfer of Eu3+ in SnO2 to perovskite. Europium ions are distributed throughout the SnO2 film during the formation process of SnO2, and they can diffuse directionally through the SnO2/perovskite interface into the perovskite, while most of the europium ions remain at the interface. Under the synergistic effect of distributed Eu3+ in the SnO2 and aggregated Eu3+ at the interface, the electron mobilities of ETLs are evidently improved. Meanwhile, diffused Eu3+ ions passivate the perovskite to reduce trap densities at the grain boundaries, which can dramatically elevate the open‐circuit voltage (Voc) of PSCs. Finally, the mainly PSCs coated on SnO2:Eu3+ ETL achieve a power conversion efficiency of 20.14%. Moreover, an unsealed device degrades by only 13% after exposure to ambient atmosphere for 84 days.

Intermediate Phase‐Free Process for Methylammonium Lead Iodide Thin Film for High‐Efficiency Perovskite Solar Cells

“…The DMSO‐based as‐coated film shows only the DMSO‐incorporated intermediate phase, evidenced by the XRD peaks at 6.8°, 7.4°, and 9.4°. [ 2 , 12 ] PVSK‐related XRD peaks are not observed at all. The DMF‐based film appears to be brown before the annealing and black after the annealing.…”

“…Over the past decade, the certified power conversion efficiency (PCE) of single‐junction PSCs has sharply increased to 25.5%. [ 1 ] The rapid improvement in PCE of PSCs is mainly accompanied by the advances in fabrication process such as solvent engineering strategy, [ 2 ] as well as the developments in desirable composition of light absorptionmaterial such as mixed‐halide and mixed cation perovskites, [ 3 ] and device configuration with new charge transport layers. [ 4 ]…”

“…This method is implemented by spin‐coating a PVSK precursor solution that is based on polar aprotic solvents, such as dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), and followed by dripping a non‐polar anti‐solvent before the end of the spin‐coating. [ 2a,b ] The anti‐solvent dripping process reduces the solubility of the PVSK salts by eliminating the miscible solvents. Therefore, an intermediate phase can be achieved by solidification and crystallization of the Lewis adduct, which is a coordination compound of a Lewis acid (e.g., PbI 2 ) and a Lewis base (e.g., DMSO) in the PVSK precursor.…”

Light‐Emitting Perovskite Solar Cells: A Tale of Two States

“…[1][2][3][4][5][6][7][8][9] Aside from photovoltaic applications, MHPs have high photoluminescence quantum efficiency (PLQY), low exciton binding energy, and high color purity, which render them an ideal candidate for the development of high-performance light-emitting diodes (LEDs). [10][11][12][13][14][15][16] Interestingly, as both perovskite LEDs and SCs have similar geometry and use the same semiconductor, therefore, perovskite light-emitting solar cells (LESCs), which can perform both functions by acting as a reversible transducer between light and electricity, hold the ultimate device architecture in the optoelectronics industry. When integrated with a rechargeable battery, these LESCs can be used in solar lamps, which harvest solar energy during the day as SCs and emit light at night as LEDs.…”

Long life Perovskite Nanoplatelet Lasers with high quality factor enabled through engineering degradation pathways

“…Perovskites have attracted considerable interests and been considered as leading candidate gain media for next generation on-chip optical sources, thanks to their outstanding photophysical properties as well as low-cost and promise for electrically driven lasing [7][8][9][10] . Among various perovskite materials, the organic-inorganic hybrid materials, with MAPbI 3 as a representative, are of particular interesting in the elds of semiconductor lasers as well as solar cells 11,12 , light emitting diodes 13 , photodetectors 14 , etc., due to their large absorption coe cient, exceptionally low trap-state densities, long charge carrier diffusion lengths, and high charge mobilities 15 .…”