Room-temperature processed tin oxide thin film as effective hole blocking layer for planar perovskite solar cells.

Tin oxide (SnO 2 ) film with high mobility and good transmittance has been reported as a promising semiconductor material for high performance perovskite solar cells (PSCs). In this study, ultrathin SnO 2 film synthesized by radio frequency magnetron sputtering (RFMS) method at room temperature was employed as hole blocking layer for planar PSCs. The room-temperature sputtered SnO 2 film not only shows favourable energy band structure but also improves the surface topography of fluorine doped SnO 2 (FTO) substrate and perovskite (CH 3 NH 3 PbI 3 ) layer. Thus, this SnO 2 hole blocking layer can efficiently promote electron transport and suppress carrier recombination. Furthermore, the best efficiency of 13.68% was obtained for planar PSC with SnO 2 hole blocking layer prepared at room temperature. This research highlights the room-temperature preparation process of hole blocking layer in PSC and has a certain reference significance for the usage of flexible and low-cost substrates. [ABSTRACT FROM AUTHOR]