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DOE OSTI · 1904855

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

Eze, Vincent Obiozo·Carani, Lucas Braga·Majumder, Haimanti·Uddin, M. Jasim·Okoli, Okenwa I.
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Abstract

Inorganic CsPbIBr 2 perovskites 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 CsPbIBr 2 perovskite 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 CsPbIBr 2 perovskite precursor solution to prepare the unique perovskite CsI(PbBr 2 ) 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 CsPbIBr 2 perovskite 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 CsPbIBr 2 perovskite films for solar cells with higher stability and other optoelectronic applications.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYelectrocatalysisphotocatalysissolar cells

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Eze, Vincent Obiozo, Carani, Lucas Braga, Majumder, Haimanti, Uddin, M. Jasim, Okoli, Okenwa I.. 2022-05-12. Inorganic cesium lead mixed halide based perovskite solar materials modified with functional silver iodide. https://doi.org/10.1038/s41598-022-11729-0

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