Oxidation states in perovskite layers formed using various deposition techniques

Organic–inorganic halide perovskites have rapidly become emerging materials for photovoltaic applications, but a major factor causing instability in perovskite solar cells could be the elemental shift due to oxygen. The present work demonstrates the oxidation states of perovskite layers formed by (i) one-step deposition, (ii) solvent-to-solvent extraction, (iii) hot casting, and (iv) mixed-cation solution processing. X-ray photoelectron...