Single-crystal CoSe2 nanorods as an efficient electrocatalyst for dye-sensitized solar cells

Abstract

Single-crystal CoSe₂ nanorods have been prepared by a facile one-step hydrothermal method. The thin CoSe₂ films fabricated by drop-casting the CoSe₂ nanorod suspension onto conductive substrates followed by simple drying without sintering can be used as a highly efficient electrocatalyst for the reduction of I₃⁻. Dye-sensitized solar cells (DSSCs) with the standard N719 dye and the single-crystal CoSe₂ nanorod cathode achieve a power conversion efficiency of 10.20% under AM1.5G one-sun illumination versus 8.17% for the Pt cathode. This finding implies that single-crystal CoSe₂ nanorods are promising low-cost and high-performance cathode materials for high-performance DSSCs.