Abstract
Development of the stable, lead-free inorganic perovskite material is of greatly importance on fabricating the third-generation solar cell. Until now, double perovskite, such as Cs2AgBiBr6, has been proved to be one of the most potential candidates to solve the toxicity and stability issues of traditional lead halide perovskite solar cells (PSCs). However, due to a wide and indirect bandgap of Cs2AgBiBr6 film, its light absorption ability is largely limited and the photoelectronic conversion efficiency (PCE) is normally lower than 2.5%. In this text, by using a hydrogenation method, the bandgap (Eg) of Cs2AgBiBr6 films could be tunable from 2.14 eV to 1.61 eV. At the same time, the highest PCE of hydrogenated Cs2AgBiBr6 perovskite solar cell has been improved more than 150% up to 6.27%. To the best of our knowledge, this is a record high efficiency of Cs2AgBiBr6-based perovskite solar cell. Further investigations confirmed that the interstitial doping of atomic hydrogen (H*) in Cs2AgBiBr6 lattice could not only adjust its valence and conduction band energy levels, but also optimize the carrier mobility from 1.71 cm2V-1s-1 to 9.28 cm2V-1s-1 and enhance the carrier lifetime from 18.85 ns to 41.86 ns. All these works provide a new strategy to fabricate the high performance lead-free inorganic PSCs.
Numerical Modeling and Optimization of Lead-Free Hybrid Double Perovskite Solar Cell by Using SCAPS-1D
