Ultrasound-spray deposition of multi-walled carbon nanotubes on NiO nanoparticles-embedded perovskite layers for high-performance carbon-based perovskite solar cells

The ultrasound spray deposition technique was adopted firstly to deposit the pure multi-walled carbon nanotubes (MWCNT) electrode on pure PbI2 or PbI2 with NiO nanoparticles sub-monolayer substrates. After the conversion reaction from PbI2 to perovskite dipping in the CH3NH3I solution, two different structures of carbon based perovskite solar cells (C-PSCs) were fabricated, with both NiO NPs and/or MWCNT implanted into the surface region of perovskite film. The integrated perovskite/carbon interfaces guaranteed the fast hole extraction and transporting, and reduced the interface nonradiative recombination process, thereby enhancing the overall photovoltaic performance.213