Platinum-Free Ternary Metallic Selenides as Nanostructured Counter Electrode for High-Efficiency Dye-Sensitized Solar Cell by Interface Engineering

The high cost and instability of platinum (Pt) counter electrodes (CEs) are two persistent issues in dye-sensitized solar cells (DSSCs). Here, ternary selenide NiCoSe and RuCoSe-nanostructured CEs are prepared by a simple one-step hydrothermal method. We mainly investigate the synergistic effect of ternary transition metals on the electrocatalytic properties. As a result, the photoelectric conversion efficiency (PCE) of NiCoSe CEs DSSCs with the enhanced efficiency up to 8.19% can be achieved. The excellent catalytic properties of the NiCoSe alloy selenide on I-3(-) can be attributed to the expanded active sites, matched work function, redistributed electron structures, and reduced interface resistance. The facile preparation approach and outstanding catalytic behaviors offer applications of available DSSCs with low cost, superior stability, and promising performance.