High-Performance Plastic Platinized Counter Electrode via Photoplatinization Technique for Flexible Dye-Sensitized Solar Cells

A photoplatinization technique was proposed to deposit Pt on a thin TiO2 layer modified indium tin oxide-coated polyethylene naphthalate (ITO/PEN) substrate at low temperature (about 50 degrees C after 1 h of UV irradiation) for the first time. The fabrication process Includes coating and hydrolyzing the tetra-n-butyl titanate to form a TiO2-modified layer and the photoplatinization of the modified substrate in H2PtCl6/2-propanol precursor solution under UV Irradiation. The obtained platinized electrodes Were used as counter electrodes (CE) for flexible dye-sensitized solar cells.(FDSCs). The well-optimized platinized electrode showed high optical transmittance, up to 76.5% between 400 and 800 nm (T-av), and the charge transfer resistance (R-ct) was as low as 0.66 Omega cm(2). A series of characterizations also demonstrated the outstanding chemical/electrochemical,durability,and mechanical stability of the platinized electrode. The FDSCs with TiO2/Ti Phatoanodes and the obtained CEs achieved a power conversion efficiency (PCE) up to 8.12% under rear-side irradiation. (AM 1.5 illumination, 100 mW cm(-2)). The obtained CEs were also employed in all-plastic bifacial DSCs. When irradiated from the rear side, the bifacial FDSC yielded a PCE of 6.26%, which approached 90% that of front-side irradiation (6.97%). Our study revealed that, apart from serving, as a functional layer for deposition of Pt, the thin TiO2 layer modification on ITO/PEN substrates also played an Important role In Improving the transparency and the mechanical properties of the CE. The effect of the thickness of the TiO2 layer for Pt coating on the performance of the CE was also investigated.