Low-Temperature and Ambient Processed All Inorganic CsPbBr₃ Perovskite Solar Cells: Stability Enhancement with AZO as an Electron Transport Layer

Abstract

All inorganic CsPbBr3-based perovskite solar cells (PSCs) have drawn great attention from researchers because of their high chemical and thermal stability in an open environment. In this work, we successfully replaced the high-temperature deposited mesoporous caping (m-TiO2) electron transport layer (ETL) with a low-temperature deposited aluminum-doped zinc oxide (AZO) ETL and fabricated all inorganic CsPbBr3 PSCs using copper­(I) thiocyanate (CuSCN) as a hole transport layer (HTL). The fabricated AZO-based devices exhibited an excellent power conversion efficiency (PCE) of 6.42%, fill factor (FF) of 60.32%, open-circuit voltage (V OC) of 1.01 V, and short-circuit current density (J SC) of 10.38 mA/cm2, whereas m-TiO2-based devices exhibited PCE of 5.33%, FF of 62.88%, V OC of 1.02 V, and J SC of 8.39 mA/cm2 under ambient conditions. In terms of stability, the AZO-based device retained 94% of its initial PCE, whereas the m-TiO2-based device retained 69% of its initial PCE after 1000 h of continuous exposure in the ambient atmosphere of relative humidity ∼81% and room temperature (RT) ∼27 °C without any encapsulation. Therefore, this approach of replacing m-TiO2 with AZO can facilitate the fabrication of efficient and highly stable planar all-inorganic PSCs in an ambient environment. In addition, we represented a cheap encapsulation process for improved stability as an additional advantage.

Simulation-Based Performance Optimization and Mechanistic Analysis of CsPbIBr2/CsPbBr3 Stacked All-Inorganic Perovskite Solar Cells in Low-Temperature Working Environments

“…Since the first use of organic–inorganic halide perovskite materials in solar cells was reported by Miyasaka and colleagues in 2009, there has been a dramatic increase in the power conversion efficiency (PCE) from 3.8% to 26.1%, − establishing these cells as a cornerstone in the next wave of photovoltaic innovations. However, extensive research has demonstrated that the presence of organic components in the perovskite layer can lead to humidity and thermal instability, especially with regards to temperature tolerance, , significantly impacting the utilization of perovskite solar cells in practical scenarios. Particularly, in the face of abrupt temperature fluctuations, the presence of organic materials may exacerbate the structural degradation of perovskite materials, thereby adversely affecting their photoelectric conversion efficiency and operational lifespan.…”