Macor, L.; Sigal, A.; Dittrich, T.; Rappich, J.; Otero, L.; Gervaldo, M.: Large electron-hole diffusion lengths in methylammonium lead triiodide perovskite films prepared by an electrochemical-chemical approach. ECS Journal of Solid State Science and Technology 6 (2017), p. P819-P821
10.1149/2.0181712jss
Abstract:
CH3NH3PbI3 perovskite films were successfully formed by chemical conversion of electro-deposited NiO/PbO2 layers stacks by simple immersion in a CH3NH3I solution under ambient conditions. Both, NiO, used as hole transport layer, and PbO2 were electrochemically grown in aqueous solutions without the use of organic solvents. The diffusion lengths in the CH3NH3PbI3 perovskite films obtained by chemical conversion of PbO2 films are nearly one order of magnitude larger than those measured in photoelectrodes produced by the standard two step spin coating methodology. The obtained values amount to about 2.4 µm what is very similar to the size of the grains (about 2 µm). The electrochemical methodology used here demonstrates the potential of this technique in the fabrication of highly homogeneous perovskite solar cells by simple immersion steps in environmental friendly solvents.