Highly Efficient Solution‐Processed Poly(3,4‐ethylenedio‐xythiophene):Poly(styrenesulfonate)/Crystalline–Silicon Heterojunction Solar Cells with Improved Light‐Induced Stability

p-Toluenesulfonic acid/dimethyl sulfoxide (PTSA/DMSO)-treated poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/crystalline-silicon (c-Si) hybrid solar cells with a solution-processed anti-reflection coating of TiO2 exhibit a record power conversion efficiency of 15.5%. Additionally, the performance stability of the hybrid device for both air storage and light exposure is improved due to removal of the PSS matrix from the PTSA/DMSO-treated PEDOT:PSS thin film.