A low-cost, activated carbon-coated, stainless-steel counter electrode for dye-sensitized solar cells

A low-cost, activated carbon (AC) and sugar-coated stainless-steel counter electrode for dye-sensitized solar cells was successfully fabricated and characterized. For performance comparison, a similar electrode was fabricated using a FTO glass as the substrate. The photovoltaic performance of dye-sensitized solar cells made with these two counter electrodes were compared with solar cells made with a Pt counter electrode. The optimized, activated carbon-coated, stainless-steel-based dye-sensitized solar cells showed an energy conversion efficiency of 8.21% while similarly optimized solar cells made with activated carboncoated FTO counter electrode showed an efficiency of 7.50%. The efficiency of corresponding solar cells made with Pt counter electrode was 9.22%. The high solar cell efficiency of 89% of that of Pt based cells can be attributed to the high electro-catalytic activity and enhanced effective surface area of activated carbon/ sugar composite and good electrical conductivity of stainless steel as demonstrated by electrochemical impedance spectroscopy, cyclic voltammetry, Tafel plot analysis and SEM imaging.