Enhancing Photovoltaic Performance and Stability of Perovskite Solar Cells through Single-Source Evaporation and CsPbBr[sub.3] Quantum Dots Incorporation

This study investigates the potential of inorganic perovskite CsPbBr[sub.3] as a photovoltaic material, highlighting its superior stability compared to that of organic-inorganic hybrid perovskite materials. Conventional methods for preparing CsPbBr[sub.3] perovskite films, such as the two-step method and the dual-source thermal evaporation method, face challenges in obtaining high-purity films due to the decomposition of precursor films and the formation of multiple heterogeneous phases. To address this issue, we synthesized CsPbBr[sub.3] powder material using thermal evaporation deposition, which effectively suppressed decomposition and the formation of heterogeneous phases. Consequently, we achieved uniform and dense CsPbBr[sub.3] perovskite films. By incorporating energy-band engineering modification with CsPbBr[sub.3] quantum dots (QDs), the all-inorganic perovskite solar cells (PSCs) attained a power conversion efficiency (PCE) of 7.01% under standard solar illumination conditions. The device PCE remained at 93% of its initial efficiency under 30% relative humidity conditions for over 100 days, showcasing its durability. The developed method produced an average grain size of 800 nm, resulting in a smooth and uniform film surface, thereby demonstrating the method's high repeatability. Additionally, the optimized PSCs exhibited a high open-circuit voltage (V[sub.OC]) with the champion device reaching a V[sub.OC] of 1.38 V and a PCE of 7.01%. This research presents a robust, efficient, and cost-effective approach for fabricating high-quality all-inorganic PSCs.