Fig. 7From: Enhanced Power Conversion Efficiency of Perovskite Solar Cells with an Up-Conversion Material of Er3+-Yb3+-Li+ Tri-doped TiO2a PL and b TRPL of perovskite layers on the mesoporous layers formed by 30NR-D without UC-TiO2 and 30NR-D with UC-TiO2Back to article page