Low-temperature interfacial engineering for flexible CsPbI2Br perovskite solar cells with high performance beyond 15%

High-efficiency flexible CsPbI₂Br PSCs are designed by introducing Al-doped ZnO as an electron-transport layer and tert-butyl cyanoacetate as a hole passivation layer. The optimized PSC exhibits outstanding stability and a champion PCE of 15.08%.