Recent Progress of Counter Electrode Catalysts in Dye-Sensitized Solar Cells

To realize long-term developments and practical application of the dye-sensitized solar cells (DSCs) requires a robust increase of the power conversion efficiency (PCE) and a significant decrease of the production cost. Fortunately, a new record PCE value of 12.3% was achieved by using cobalt-based redox couples combined with organic dye. Evidently, dye design is the key path to improve the PCE, while developing low cost counter electrode (CE) catalysts is one of the promising paths to reduce the production cost of DSCs by replacing the expensive Pt CE. In this article, we review the recent progress of CE catalysts involving Pt, carbon materials, inorganic materials, multiple compounds, polymers, and composites. We discuss the advantages and disadvantages of each catalyst and put forward ideas for designing new CE catalysts in future research for DSCs and other application fields.