Moisture assisted CsPbBr3 film growth for high-efficiency, all-inorganic solar cells prepared by a multiple sequential vacuum deposition method

We developed a multiple sequential vacuum deposition method for the preparation of CsPbBr 3 film with pure phase. Meanwhile, we found the annealing humidity plays an important role for the growth of CsPbBr 3 crystal. By controlling the relative humidity at 30%, we obtained high-quality CsPbBr 3 film with large grain size. As a result, a PCE of 8.86% has been achieved in the all-inorganic PSCs with a planar structure of FTO/compact TiO 2 /CsPbBr 3 /carbon.