Open Access

ARTICLE

Effectively Inhibit Phase Separation to Improve Efficiency and Stability of All-Inorganic Planar CsPbIBr₂ Perovskite Solar Cells

Miao He^*, Miao Wu^#, Duofa Wang, Tianjin Zhang^*

Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, Hubei Key Laboratory of Polymer Materials, School of Materials Science and Engineering, Hubei University, Wuhan, 430062, China

* Corresponding Authors: Tianjin Zhang. Email: ; Miao He. Email:
# This author contributed equally to this work and should be considered co-first author

(This article belongs to the Special Issue: Perovskite Solar Cells)

Journal of Renewable Materials 2022, 10(11), 2883-2894. https://doi.org/10.32604/jrm.2022.020535

Received 30 November 2021; Accepted 25 January 2022; Issue published 29 June 2022

Abstract

The advancement in a power conversion efficiency (PCE) to reach 25%, the inorganic perovskites are being explored intensively as promising optoelectronic materials due to their excellent photovoltaic performance, i.e., thermal stability and efficiency. Lately, the inorganic cesium lead halide perovskite is studied to show enhanced light absorption, however, it suffers from the phase separate into I-rich and Br-rich phase which leads to poor film quality due to difference of electronegativity. Herein, we propose a unique solution of controlling the rate of solvent volatilization followed by gel method to inhibit phase separation effectively to obtain the homogenous and pinhole-free CsPbIBr₂ films with high crystalline quality. In this study, an inverted planar device based on a light absorber of CsPbIBr₂ is prepared to achieve a power conversion efficiency of 8.8% (maintain a stabilized value of 8% in ambient air conditions). Surprisingly, the optimized cell without encapsulation shows excellent long-term stability, as it maintained 90% initial efficiency over 500 h and controlled storage at around 45% relative humidity and 25°C.

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Keywords

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