Enhanced Performance for Planar Perovskite Solar Cells\nwith Samarium-Doped TiO₂ Compact Electron Transport Layers

Abstract

The\ntactics of ion doping in metal oxide is normally used to improve\nthe film quality, achieve an appropriate energy band, and enhance\ncarrier mobility. Here, a rare earth element (samarium) was doped\ninto TiO₂ compact electron transport layers (ETLs) by adding\nsamarium trinitrate into the titanium precursor solution. The results\nshow that perovskite solar cells (PSCs) with Sm-doped TiO₂ exhibit 10.3% enhancement with a power conversion efficiency (PCE)\nof 14.10%, compared to nondoped devices. It is found that Sm doping\ncan upward shift the Fermi energy level of the ETLs, increase the\ncarrier transport ability, and inhibit the carrier recombination.\nThe results indicate that rare earth ion doping could be a promising\nmethod for producing effective ETLs and high performance PSCs.