CH 3 NH 3 PbBr 3 –CH 3 NH 3 PbI 3 Perovskite–Perovskite Tandem Solar Cells with Exceeding 2.2 V Open Circuit Voltage

Perovskite-perovskite tandem solar cells with open-circuit voltages of over 2.2 V are reported. These cost-effective, solution-processible perovskite hybrid tandem solar cells with high open-circuit voltages are fabricated by the simple lamination of a front planar MAPbBr3 perovskite cell and a back MAPbI3 planar perovskite solar cell.