NiCo-LDH nanosheets strongly coupled with GO-CNTs as a hybrid electrocatalyst for oxygen evolution reaction

The rational fabrication of highly efficient electrocatalysts with low cost toward oxygen evolution reaction (OER) is greatly desired but remains a formidable challenge. In this work, we present a facile and straightforward method of incorporating NiCo-layered double hydroxide (NiCo-LDH) into GO-dispersed CNTs (GO-CNTs) with interconnected configuration. X-ray absorption spectroscopy (XAS) reveals the strong electron interaction between NiCo-LDH and the underlying GO-CNTs substrate, which is supposed to facilitate charge transfer and accelerate the kinetics for OER. By tuning the amount of CNTs, the optimized NiCo-LDH/GO-CNTs composite can achieve a low overpotential of 290 mV at 10 mA.cm(-2) current density, a small Tafel slope of 66.8 mV.dec(-1) and robust stability, superior to the pure NiCo-LDH and commercial RuO2 in alkaline media. The preeminent oxygen evolution performance is attributed to the synergistic effect stemming from the merits and the intimate electron interaction between LDH and GO-CNTs. This allows NiCo-LDH/GO-CNTs to be potentially applied in an industrial non-noble metal-based water electrolyzer as the anodic catalysts.

Automated summary

In this work, a facile method of incorporating NiCo-layered double hydroxide (NiCo-LDH) into GO-dispersed CNTs (GO-CNTs) with interconnected configuration was presented, showing superior oxygen evolution performance. The optimized NiCo-LDH/GO-CNTs composite exhibited low overpotential, small Tafel slope, and robust stability in alkaline media, outperforming pure NiCo-LDH and commercial RuO2. The excellent oxygen evolution performance was attributed to the synergistic effect and intimate electron interaction between LDH and GO-CNTs, suggesting potential industrial applications in non-noble metal-based water electrolyzers.