Recent research trends in inorganic charge transport materials for next-generation perovskite solar cells

Perovskite solar cells (PSC) have recently garnered significant attention in solar energy research, recording power conversion efficiency (PCE) exceeding 26.95 %. These devices are noted for their simple fabrication and cost-effectiveness, marking them as a promising next-generation solar cell technology. However, commercialization is still hindered by stability and performance issues. In PSCs, charge transport materials play a crucial role in enhancing PCE by suppressing charge recombination and protecting the perovskite material from heat and humidity, thereby ensuring long-term stability. Inorganic materials with a perovskite structure exhibit excellent light absorption and charge transport efficiency, making them vital in optoelectronic applications. By applying doping or passivation to inorganic materials and designing composites with organic materials, both efficiency and stability can be improved simultaneously. This review aims to elucidate and analyze the roles and properties of n-type and p-type inorganic materials in addressing efficiency and stability issues in PSCs. Additionally, it provides an in-depth understanding of various charge transport materials (CTM) to inspire the development of future CMT models.