Surface Reconstruction of Lead-Free Perovskite Cs 2 Ag 0.6 Na 0.4 InCl 6 :Bi by Hydroxylation with Blue-Light-Excited Performance

• Published in: Journal of colloid and interface science 2023-10, Vol.648, p.865
• Main Authors: Gong, Xiao-Kai, Zhang, Xiao-Song, Li, Qian, Liu, Long, Zhang, Yue-Ming, Li, Chao, Kong, Li-Na, Xu, Jian-Ping, Li, Lan
• Format: Article
• Language: English
• ISSN: 1095-7103

Molecular surface reconfiguration strategies have been instrumental to performance improvements of halide perovskite photovoltaic applications in recent years. However, research into the optical properties of the lead-free double perovskite Cs AgInCl on the complex reconstructed surface is still lacking. Here, blue-light excitation in double perovskite Cs Na Ag InCl with Bi doping has been successfully achieved by excess KBr coating and ethanol-driven structural reconstruction. Ethanol drives the formation of hydroxylated Cs K Ag Na In Bi Cl Br in the Cs Ag Na In Bi Cl @xKBr interface layer. The hydroxyl group adsorbed on the interstitial sites of the double perovskite structure induces a transfer of local space electrons to the [AgCl ] and [InCl ] octahedral regions, enabling them to be excited with blue light (467 nm). The passivation of KBr shell reduces the non-radiative transition probability of excitons. Blue-light-excited flexible photoluminescence devices based on hydroxylated Cs Ag Na In Bi Cl @16KBr are fabricated. The application of hydroxylated Cs Ag Na In Bi Cl @16KBr as down-shift layer in GaAs photovoltaic cell module can increase its power conversion efficiency by 3.34%. The surface reconstruction strategy provides a new way to optimize the performance of lead-free double perovskite.