【摘要】：In recent years, due to their high photo-to-electric power conversion efficiency(PCE)(up to 23%(certified)) and low cost, perovskite solar cells(PSCs) have attracted a great deal of attention in photovoltaics field. The high PCE can be attributed to the excellent physical properties of organic–inorganic hybrid perovskite materials, such as a long charge diffusion length and a high absorption coefficient in the visible range. There are different diffusion lengths of holes in electrons in a PSC device, and thus the electron transporting layer(ETL) plays a critical role in the performance of PSCs. An alternative for TiO_2, to the most common ETL material is SnO_2, which has similar physical properties to TiO_2 but with much higher electron mobility, which is beneficial for electron extraction. In addition, there are many facile methods to fabricate SnO_2 nanomaterials with low cost and low energy consumption. In this review paper, we focus on recent developments in SnO_2 as the ETL of PSCs. The fabrication methods of SnO_2 materials are briefly introduced. The influence of multiple Sn O_2 types in the ETL on the performance of PSCs is then reviewed. Different methods for improving the PCE and long-term stability of PSCs based on SnO_2 ETL are also summarized. The review provides a systematic and comprehensive understanding of the influence of different Sn O_2 ETL types on PSC performance and potentially motivates further development of PSCs with an extension to SnO_2-based PSCs.