3P-227 : Thermally stable inorganic CsPbI2Br perovskite solar cells

We demonstrated a highly efficient and thermally stable inorganic CsPbI2Br MHP solar cells using with a P3HT hole transporting layer by spin-washing of the P3HT HTL since the light harvesting efficiency is improved by minimizing the co-absorption of light by P3HT, and Voc is enhanced because of the increased valence band maximum position of the spin-washed P3HT HTL. The spin-washed CsPbI2Br MHP solar cell exhibited 1.24V Voc, 14.20mA/cm2 Jsc, 81.52% FF, and 14.35% PCE. The unencapsulated spin-washed CsPbI2Br MHP solar cell went through 7.56% degradation after a 1000h thermal stability test under 100°C/25% relative humidity (RH) and simultaneous 1 sun light soaking conditions. In addition, the unencapsulated spin-washed CsPbI2Br MHP solar submodule with 25 cm2 of masked active area showed a 98% geometrical FF, 115.09mA Isc, 3.54V Voc, 71.09% FF, and 11.58% PCE while exhibiting 8.80% of degradation during a thermal stability test at 100℃/25% RH and 1 sun light soaking for 1000h.