Progress in High-Efficiency Inverted Perovskite Solar Cells: Charge Transport, Interface Engineering, and Stability

Inverted (p-i-n) perovskite solar cells (PSCs) have emerged as a focal point in photovoltaic research, combining high efficiency with long-term stability and offering a strong potential for tandem integration. Their quasi-steady-state certified power conversion efficiencies (PCEs) now exceed 27%, surpassing those of their regular (n-i-p) counterparts. Here, we review recent advances in high-performance p-i-n PSCs, highlighting strategies for the selection and optimization of charge-transport layers, regulation of perovskite crystallization, and design of interface engineering. Finally, we discuss the significant breakthroughs in the stability of p-i-n PSCs and provide an outlook on future directions that may guide the next stage of device optimization, thereby laying the foundation for the large-scale implementation of perovskite photovoltaics.