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

• Use of nano assembled TiO2 submicron beads in perovskite solar cell.
• Light harvesting effect through enhanced grain growth of perovskite crystallites.
• Significant improvement in cell conversion efficiency as compared to conventional mesoporous TiO2.

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 TiO2 layer, we have modified the surface microstructuring of the TiO2 film by dispensing nano assembled TiO2 submicron structures (nanobeads, NBs) on TiO2 compact layer. With this new approach solar cell efficiency was improved significantly through an increase in both Jsc and Voc. 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.

Herein a new variant of surface microstructuring is introduced in the perovskite solar cell architecture to enhance the CH3NH3PbI3 loading and mean crystallite size. This enhancement leads to enhanced light harvesting, leading to higher current density (Jsc) as well as higher Voc by reducing carrier recombination.Figure optionsDownload as PowerPoint slide