Critical analysis of recent advancements in incorporating Cs in hybrid perovskite solar cell to boost its stability and efficiency

Perovskite solar cells (PSCs) are revolutionizing the field of renewable energy (RE) production due to their extraordinary PV responses and affordable large–scale production. It has garnered significant curiosity owing to its distinctive features, including as enhanced light harvesting, carrier transport, and relatively simple production. In this regard, Hybrid organic–inorganic perovskites (HOIP) are attracting considerable interest as photon harvesters in PV cells because of their substantial improvements in power conversion efficiency (PCE). This article fundamentally addresses the PV performances, PCEs, short and long-term stability issues, and practical challenges and benefits associated with the Caesium (Cs) incorporation into the HOIP mono– and mixed–halide solar cells. Additionally, we have analysed the material characterises, device physics, fabrication processes and the underlying degradation mechanisms of Cs-HOIP structures, focusing on the device optimization for ensuring enhanced stability and efficiency as well as improved electrical performances. Finally, we have offered insights on the future commercialization trajectory for large–area Cs–HOIP PSCs, emphasizing the significance of improved stability and better efficiency with convenient fabrication processes for the broad acceptance of this promising technology. This review thoroughly examines high-efficiency HOIP solar cells, emphasizing essential elements such device designs, fabrication methods, solvent engineering and defect passivation, as well as recent developments and challenges.