Enhancing efficiency of perovskite solar cell via surface microstructuring: Superior grain growth and light harvesting effect

Abstract We have introduced a novel approach to enhance the perovskite solar cell efficiency by controlling the grain growth and light harvesting properties of perovskite crystallites. Instead of using a mesoporous TiO 2 layer, we have modified the surface microstructuring of the TiO 2 film by dispensing nano assembled TiO 2 submicron structures (nanobeads, NBs) on TiO 2 compact layer. With this new approach solar cell efficiency was improved significantly through an increase in both J sc and V oc . This high efficiency is attributed to crystallite size of the perovskite phase. These also act as light scattering centers giving higher current density and reduced recombination effects giving higher open circuit voltage.