Reducing the Trap Density in MAPbI3 Based Perovskite Solar Cells via Bromide Substitution. Issue 4 (7th April 2022)

• Record Type: Journal Article
• Authors: Pegu, Meenakshi; Ghaderian, Abolfazl; Ahmad, Shahzada; Kazim, Samrana
• Is Part Of: ChemPlusChem. Volume 87:Issue 4(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-04-07
• Subjects: device stability -- halide exchange -- perovskites -- solar cells -- trap density; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cplu.202200021
• Languages: English
• ISSNs: 2192-6506

Abstract

Abstract: The past decade has witnessed tremendous advancement in the field of halide perovskite (PSK) as a choice of material for high‐performing solar cells fabrication. Here, we investigate the impact of the halide exchange through N ‐bromosuccinimide ( NBS ) treatment in MAPbI3 based solar cells. We observed the partial halide exchange (I − to Br − ) or the filling of halide (X − ) vacancy upon treatment of different NBS concentrations experimentally by spectroscopic and diffractogram studies. We noted that halide exchange impacts the crystallization and is beneficial in improving the photovoltaic performance. The optimized 0.5 % NBS treated PSC exhibited a power conversion efficiency of 17.87 % due to an increment in open‐circuit voltage ( V oc ) and short circuit current ( J sc ). We noted improved perovskite crystal growth upon Br − substitution; eventually, it helps to lower the trap density, reducing non‐radiative recombination and renders the enhancement of long‐term stability of PSC. Abstract : A simple approach of passivating the perovskite surface is reported using an N ‐bromosuccinimide (NBS) in isopropanol generating HBr that induces I − /Br − exchange in the perovskite layer. The generation of HBr further assists in crystallinity by bromide substitution in MAPbI3, reduces defects, and improves solar cell performance for optimized concentration.