Electrospray-Deposited Poly(3,4-ethylenedioxythiophene):Poly(styrene sulfonate) for Poly(3-hexylthiophene):Phenyl-C₆₁-Butyric Acid Methyl Ester Photovoltaic Cells

Electrospray-deposited poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) was investigated using several solvent solutions as a hole-transporting layer for spin-coated poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C₆₁ butyric acid methyl ester (P3HT:PCBM) mixture organic thin-film solar cells (OSCs). Among them, the uniform deposition of PEDOT:PSS films was realized using 70% N,N-dimethylformamide solvent solution. The P3HT:PCBM solar cells with electrospray-deposited PEDOT:PSS as a hole transport layer showed a relatively high performance with an open-circuit voltage V_oc of 0.47 V, a short-circuit current J_sc of 8.9 mA/cm², a fill factor FF of 0.48, and a power conversion efficiency of 2.0%, which were almost the same as those with a spin-coated PEDOT:PSS layer. These findings imply that the electrospray-deposited PEDOT:PSS is a possible material for use as a hole transport layer for conjugated polymer-based OSCs.