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Title: Inorganic cesium lead mixed halide based perovskite solar materials modified with functional silver iodide
Abstract

Inorganic CsPbIBr2perovskites have recently attracted enormous attention as a viable alternative material for optoelectronic applications due to their higher efficiency, thermal stability, suitable bandgap, and proper optical absorption. However, the CsPbIBr2perovskite films fabricated using a one-step deposition technique is usually comprised of small grain size with a large number of grain boundaries and compositional defects. In this work, silver iodide (AgI) will be incorporated as an additive into the CsPbIBr2perovskite precursor solution to prepare the unique perovskite CsI(PbBr2)1-x(AgI)x.The AgI additive in the precursor solution works as a nucleation promoter which will help the perovskite to grow and merge into a continuous film with reduced defects. With detailed characterizations, we found that incorporating AgI additive resulted in a uniform perovskite film with fewer grain boundaries, increased grain size, crystallinity, optical absorption while decreasing carrier recombination and trap density. Using the AgI in an optimum amount, we fabricated CsPbIBr2perovskite solar cells (PSCs) with a simple structure and achieved a power conversion efficiency (PCE) of 7.2% with a reduced hysteresis index. This work offers an alternative approach towards preparing high-quality CsPbIBr2perovskite films for solar cells with higher stability and other optoelectronic applications.

 
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PAR ID:
10366962
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Scientific Reports
Volume:
12
Issue:
1
ISSN:
2045-2322
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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