Efficiency improvement of P3CT-Na based MAPbI₃solar cells with a simple wetting process

The averaged power conversion efficiency of polyelectrolytes (P3CT-Na) based MAPbI₃solar cells can be increased from 14.94% to 17.46% with a wetting method before the spin-coating process of MAPbI₃precursor solutions. The effects of the wetting process on the surface, structural, optical and excitonic properties of MAPbI₃thin films are investigated by using the atomic-force microscopic images, x-ray diffraction patterns, transmittance spectra, photoluminescence spectra and Raman scattering spectra. The experimental results show that the wetting process of MAPbI₃precursor solution on top of the P3CT-Na/ITO/glass substrate can be used to manipulate the molecular packing structure of the P3CT-Na thin film, which determines the formation of MAPbI₃thin films.