A multi-dimensional hierarchical strategy building melamine sponge-derived tetrapod carbon supported cobalt–nickel tellurides 0D/3D nanohybrids for boosting hydrogen evolution and triiodide reduction reaction

Designing efficient nanohybrid electrocatalysts with advanced structure is of great essential for energy conversion devices. Herein, a multi-dimensional hierarchical strategy is proposed to design melamine sponge-derived sulfur and nitrogen co-doped tetrapod carbon (SNTC) supported cobalt-nickel telluride (CoTe2/SNTC, NiTe2/SNTC, and CoNiTe2/SNTC) 1D/3D and 0D/3D nanohybrids for boosting hydrogen evolution reaction (HER) and triiodide reduction reaction (IRR). Among these, the CoNiTe2/SNTC 0D/3D hybrid exhibited superior catalytic activities and excellent electrochemical stability. In alkaline HER, the CoNiTe2/SNTC catalyst had a low Tafel slope of 72 mV dec-1, which was comparable to that of Pt/C (49 mV dec-1). CoNiTe2/SNTC served as counter electrode catalyst in photovoltaics and obtained a power conversion efficiency (PCE) of 8.11%, which is higher than that of Pt (7.25%). This investigation provides a novel approach for designing highly efficient nanohybrid catalysts in advanced energy devices.