Solution synthesis and phase control of inorganic perovskites for high-performance optoelectronic devices

An efficient method to synthesize well-crystallized inorganic cesium lead halide perovskites (CsPbX₃, X = I or Br) with high yield and high reproducibility was proposed. Notably, the as-prepared CsPbI₃ in the yellow orthorhombic phase (y-CsPbI₃) can be easily converted to the black cubic perovskite phase CsPbI₃ (b-CsPbI₃) after thermal annealing. Furthermore, two-terminal photodetectors and all-inorganic perovskite solar cells based on b-CsPbI₃ were fabricated, exhibiting high performances.