Recent Progresses on Defect Passivation toward Efficient Perovskite Solar Cells

Abstract

The disorderly distribution of defects in the perovskite or at the grain boundaries, surfaces, and interfaces, which seriously affect carrier transport through the formation of nonradiative recombination centers, hinders the further improvement on the power conversion efficiency (PCE) of perovskite solar cells (PSCs). Several defect passivation strategies have been confirmed as an efficient approach for promoting the performance of PSCs. Herein, recent progress in the defect passivation toward efficient perovskite solar cells are summarized, and a classification of common passivation strategies that elaborate the mechanism according to the location of the defects and the type of passivation agent is presented. Finally, this review offers likely prospects for future trends in the development of passivation strategies.

Multifunctional Phosphorus‐Containing Lewis Acid and Base Passivation Enabling Efficient and Moisture‐Stable Perovskite Solar Cells

“…These surface defects also lead to band bending and Fermi energy pinning, limiting the open‐circuit voltage ( V OC ). [ 11 ] Second, light‐, thermal, and moisture‐ induced degradation are still unavoidable for MLMP devices, and defect‐driven phase segregation (halide segregation) is one of the most concern issues. Photoinduced phase segregation is caused by charge trapping at surface defects because induced electric fields can speed up the movement and accumulation of halide ionic defects, although it is usually considered as an intrinsic property of certain perovskite based on thermodynamic model.…”

“…[ 2,18–27 ] However, it is still difficult to accurately identify defect types including Pb 2+ /halide vacancies, interstitial Pb 2+ /halides, and undercoordinated Pb 2+ /halides for these multicomponent perovskites. [ 11,28–30 ] Therefore, identifying defect types and adopting suitable passivators are crucial not only to boost the efficiency but also to slow down the moisture degradation.…”

Surface Passivation of Perovskite Film by Sodium Toluenesulfonate for Highly Efficient Solar Cells

“…Organolead halide perovskites with a general chemical formula of APbX 3 (A = Cs + , CH 3 NH 3 + (MA + ) or H 2 NCH = NH 2 + (FA + ); X = I − , Br − , Cl − ) represent emerging optoelectronic materials with the advantages of large absorption coefficients, ease of manufacture, small exciton binding energies, long charge carrier diffusion lengths, and tunable bandgaps . Using organolead halide perovskites as light absorbers, organic–inorganic hybrid perovskite solar cells (PSCs) have been attracting widespread attention.…”

Recent Advances of Device Components toward Efficient Flexible Perovskite Solar Cells

“…It is worth noting that within the common heterostructure of PSC devices, interfaces play an important role in determination of device performance, as losses of charge carriers usually occur at interfaces between different materials, leading to a reduction in both current and voltage, thus the final PCE. [53][54][55][56][57][58] Matching and fabricating device structural components of appropriate optoelectronic and photonic properties are crucial for the following assembly of devices; and this is a research focus in both conventional perovskite-based applications and flexible perovskite devices. We also expect that our Review of recent advances of device structural components may help to broaden horizons in the future development of FPSCs.…”