posted on 2021-10-20, 14:38authored byTianyuan Luo, Gang Ye, Xiayan Chen, Manman Ding, Tian Ye, Chunyan Zhao, Wenfeng Zhang, Haixin Chang
The
degeneration of organic–inorganic hybrid perovskite
solar cells (PSCs) under ambient air is a serious challenge that prevents
the commercialization of PSCs. The introduction of hydrophobic long-chain
organic cations into the perovskite film is a promising way to improve
the long-term stability of devices. However, this approach always
comes with the sacrifice of the power conversion efficiency (PCE).
In this work, we introduce a novel one-step double ion passivation
route together using phenylethylamine ion (PEA+) and SCN– to passivate the grain boundary and surface of the
perovskite polycrystalline film by crystal engineering to fabricate
all air-processed, stable PSCs. Compared with three-dimensional (3D)
MAPbI3 perovskite films, the PEA+ and SCN– codoped MAPbI3 perovskite films from the
single crystal engineering have a larger grain size and better stability
with a longer carrier lifetime and lower electron trap state density.
The champion PCE of 18.04% with negligible hysteresis was achieved
for the 0.05 M PEA+ and SCN– codoped
PSCs, which exhibit 25% higher efficiency than the MAPbI3 solar cell fabricated using the traditional precursor solution mixing
method. The devices without encapsulation still maintain 82% of their
original PCE when stored over 750 h under ambient air conditions with
a relative humidity of 50%.