Preparation of High Transmittance Platinum Counter Electrode at an Ambient Temperature for Flexible Dye-Sensitized Solar Cells

•We prepared high transmittance catalytic Pt nanoparticles on ITO/PEN by spray coating at an ambient temperature of 40°C.•The electrocatalytic behavior of 1.8 wt% nano-Pt CE shows high i0 and low Rct.•The Ti foil sub-module DSSC with 1.8 wt% nano-Pt counter electrode shows high conversion efficiency of 7.47%.•The MPN based sub-module DSSC with 1.8 wt% nano-Pt counter electrode maintains >90% after 2000hrs continuous one sun light soaking at 60°C.