Highly efficient telluride electrocatalysts for use as Pt-free counter electrodes in dye-sensitized solar cells

Abstract

Two transition metal tellurides, CoTe and NiTe₂, were synthesized and for the first time employed as the counter electrodes (CEs) with high catalytic activity for reduction of I₃⁻ in dye-sensitized solar cells (DSCs). Using CoTe and NiTe₂-based CEs, photoelectric conversion efficiencies (PCEs) of 6.92% and 7.21% were achieved for DSCs, respectively, comparable to that of 7.04% achieved when using a Pt-based CE. The results indicated that, serving as a CE in DSCs, telluride could be a cost-effective and efficient alternative to the noble metal Pt.