| abstract |
A process of forming a thin film photoactive layer of a perovskite photoactive device comprising: applying at least one coating of a perovskite precursor solution and a polymer additive to a substrate, wherein the at least one perovskite precursor solution comprises at least one reaction constituent for forming at least one perovskite compound having the formula AMX 3 dissolved in a coating solvent selected from at least one polar aprotic solvent, the polymer additive being soluble in said coating solvent, and in which A comprises an ammonium group or other nitrogen containing organic cation, M is selected from Pb, Sn, Ge, Ca, Sr, Cd, Cu, Ni, Mn, Co, Zn, Fe, Mg, Ba, Si, Ti, Bi, or In, and X is selected from at least one of F, Cl, Br or I. |