Embedding SnO 2 Thin Shell Protected Ag Nanowires in SnO 2 ETL to Enhance the Performance of Perovskite Solar Cells.

The energy level mismatching between SnO and perovskite and the nonradiative recombination at SnO-perovskite interface severely degrade the extraction of carriers, reducing the power conversion efficiency (PCE) and stability of planar perovskite solar cells (PSCs) based on SnO electron transfer layer (ETL). In the present work, a reinforced SnO ETL was successfully developed by embedding SnO thin shell protected Ag nanowires (Ag/SnO NWs) in traditional planar SnO film, which was proved to not only lower the conduction band of SnO to adjust the energy level matching, but also significantly reduce the interfacial carrier recombination. Moreover, Ag/SnO NWs improved the electrical conductivity of SnO ETL, and effectively promoted carrier transport. Benefiting from the use of Ag/SnO NWs, our newly designed PSC achieved a significantly increased champion PCE of 19.78%, which is 7% higher than the traditional PSC without Ag/SnO NWs embedding, indicating its great application potential in PSCs.