Effects of sputtering power of SnO2 electron selective layer on perovskite solar cells

Efficient perovskite solar cell (PSC) with SnO2 electron selective layer (ESL) prepared by radio frequency magnetron sputtering method at room-temperature has been realized. In this work, we systematically discussed the effect of sputtering power and surface roughness of SnO2 ESL on the photoelectric performance of planar PSC. This research shows that PSC based on SnO2 ESL sputtered at the low power of 60W exhibits the better photoelectric properties than that based on SnO2 ESL sputtered at the high power of 120W. The lower sputtering power can decrease the surface roughness of SnO2 ESL and improve the contact interface between perovskite layer and ESL, leading to the reduced carrier recombination and enhanced charge transfer property of planar PSC. Thus, with the decreased sputtering power from 120 to 60W, the photoelectric conversion efficiency of the corresponding PSC increased from 8.19 to 12.58%.