Impact of concentration of DMF and H2O on photovoltaic properties of SnO2-based planar perovskite solar cells

Abstract

SnO2-based planar perovskite solar cells were prepared via the sol-gel method and DMF was used to coordinate with SnCl4 which ensures to form a stable Sn-sol. A certain amount of H2O was added to induce SnCl4 to convert to SnO2 and reduce the remaining of OH− and Cl− on the surface of SnO2 film. Compared with the PCE of pristine SnO2-based cells (17.14%), the W-SnO2-based cell in revers scan under simulated AM1.5G illumination increases to 19.07%. The open-circuit voltage of the W-SnO2-based cells increases to 1128 mV, compared with that of the pristine SnO2-based cell (1090 mV). The unencapsulated cells maintain 90% of initial efficiency after stored in Ar glovebox for 30 days.