Stabilizing the cubic perovskite phase of CsPbI3 nanocrystals by using an alkyl phosphinic acid

CsPbI3 nanocrystals suffer from a facile cubic perovskite to orthorhombic phase transformation, which deteriorates their appealing optoelectronic properties. Here, we report a new colloidal synthesis that replaces the conventionally used oleic acid with an alkyl phosphinic acid to grow high-quality, phase-stable cubic perovskite CsPbI3 nanocrystals.