Recent advances in enhancing efficiency and stability of perovskite solar cells: a comprehensive review

Perovskite solar cells (PSCs) have emerged as one of the most promising next-generation photovoltaic technologies, achieving certified power conversion efficiencies (PCEs) exceeding 26% within little more than a decade of active research. Their tunable optoelectronic properties, compositional versatility, and compatibility with low-temperature, solution-based manufacturing routes position them as strong candidates for both standalone and tandem photovoltaic applications. Despite this extraordinary progress, two overarching challenges-insufficient long-term operational stability and the absence of scalable, reproducible manufacturing processes-continue to impede commercialization. This review addresses these challenges within the structural and compositional foundation of perovskite absorbers, covering crystal chemistry, ABX₃ stoichiometry variants, and the principal device architectures (n-i-p, p-i-n, mesoporous, and planar). Also, the intrinsic optical and electronic factors governing device efficiency, including bandgap engineering, charge-carrier dynamics, recombination mechanisms, and charge-transport physics were surveyed. Also, efficiency-enhancement strategies such as novel fabrication techniques (spin-coating, blade coating, slot-die coating, vapor deposition, and VASP), light-absorption optimization through additive and compositional engineering (ionic liquids, Lewis acid/base additives, and mixed-cation/halide systems), defect passivation approaches (alkali-ion incorporation, coordination-chemistry passivants, and surface treatments), and charge-transport layer optimization (SnO₂- and ZnO-based ETLs, dopant-free HTMs) were surveyed systematically. Importantly, the principal stability challenges-moisture ingress, UV-induced degradation, thermal decomposition, and mechanical stress-alongside the corresponding mitigation strategies, including two-dimensional/three-dimensional heterostructures, hydrophobic surface coatings, thermal stabilizers, and encapsulation technologies were investigated. A comparative analysis of all strategies with respect to demonstrated performance, key limitations, and scalability is provided in tabular form. Finally, a forward-looking perspective on commercial viability, identifying the critical technology-readiness milestones required to transition PSCs from laboratory champions to industrially deployable, environmentally responsible photovoltaic modules, were reviewed.