Boosting the hydrogen evolution of layered double hydroxide by optimizing the electronic structure and accelerating the water dissociation kinetics

Designing a highly efficient and durable electrocatalyst for hydrogen evolution reactions (HER) is of great significance to promote the development of green hydrogen energy. This work reports a vertical-aligned electrocatalyst of Cu2O/CoCu-LDH inlaid bilayer nanosheets that achieve excellent alkaline HER performance with a low overpotential of 96 mV at 10 mA cm-2 and a low Tafel slope of 76.8 mV dec- 1. Notably, Cu2O/CoCu-LDH outperforms Pt/C at a practical current density of 600 mA cm-2. The structural characterizations and theory calculations revealed that the superior HER activity of Cu2O/CoCu-LDH is due to the distinctive morphology, optimized electronic structure and accelerated water dissociation kinetics. Remarkably, the Cu2O/CoCu-LDH acted as the cathode in alkaline Zn-H2O cell demonstrating the potential applications for H2 generation and electricity energy simultaneously. Our work can guide the design of LDH-based electrocatalysts with outstanding HER performance.

Automated summary

Designing a highly efficient and durable electrocatalyst is crucial for advancing green hydrogen energy. This study presents a Cu2O/CoCu-LDH bilayer electrocatalyst with vertical-aligned nanosheets, exhibiting excellent alkaline HER performance. The Cu2O/CoCu-LDH outperforms Pt/C at 600 mA cm-2, with a low overpotential and Tafel slope. The unique morphology, optimized electronic structure, and enhanced water dissociation kinetics contribute to its superior HER activity.