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 (CoTe/SNTC, NiTe/SNTC, and CoNiTe/SNTC) 1D/3D and 0D/3D nanohybrids for boosting hydrogen evolution reaction (HER) and triiodide reduction reaction (IRR). Among these, the CoNiTe/SNTC 0D/3D hybrid exhibited superior catalytic activities and excellent electrochemical stability. In alkaline HER, the CoNiTe/SNTC catalyst had a low Tafel slope of 72 mV dec, which was comparable to that of Pt/C (49 mV dec). CoNiTe/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.