Solvothermal synthesis of highly crystalline SnO₂ nanoparticles for flexible perovskite solar cells application

Flexible perovskite solar cells are arising researchers’ attentions due to their promising potential applications. In this letter, homogeneous and highly crystalline SnO₂ nanoparticles are successfully synthesized by a solvothermal method, which are then employed to deposit high quality electron transport layers by spin coating and baking at a temperature as low as 150 °C. The prepared SnO₂ layer has a homogenous and flat surface without any pinholes. The resulting flexible perovskite solar cell shows a high power conversion efficiency of 13.90%, which is mainly attributed to the good transmittance, efficient electron extraction and hole blocking ability of the SnO₂ electron transport layer.