CoTe2-NiTe2 heterojunction directly grown on CoNi alloy foam for efficient oxygen evolution reaction

The development of high-efficiency and durable non-noble metal-based oxygen evolution reaction (OER) electrocatalysts is a particularly urgent need for electrochemical water splitting. An effective electrocatalyst can be prepared by tailoring the composition, morphology, and structure of the material. Herein, we report a CoTe2-NiTe2 heterojunction directly grown on CoNi alloy foam (CNF) via a simple hydrothermal route. The optimized electrode of 3CNT/CNF-240C was achieved through the adjustment of reductant addition of N2H4 center dot H2O and the reaction temperature in the hydrothermal reaction. The 3CNT/CNF-240C electrode only needs a low overpotential of 280 mV to attain an anodic current density of 10 mA cm(-2), and shows fast kinetics for the OER with a small Tafel slop of 19.4 mV dec(-1). The enhanced OER performance could be attributed to the interaction between CoTe2 and NiTe2 in the heterojunctions promoting the charge transfer process. Moreover, 3CNT/CNF-240C also shows excellent long-term stability, which can maintain 18 h of continuous electrolysis without obvious degradation. Our research provides a new strategy for the direct synthesis of integrated hybrid structured electrocatalysts to achieve highly active and durable water splitting.

Automated summary

The research has successfully developed a high-efficiency and durable non-noble metal-based oxygen evolution reaction (OER) catalyst by growing a CoTe2-NiTe2 heterojunction on CoNi alloy foam, preparing an optimized electrode through hydrothermal method, achieving high OER activity, and demonstrating excellent stability.