Electrocatalytic hydrogen evolution reaction on graphene supported transition metal-organic frameworks

A highly efficient, cost-effective, and durable electrocatalysts based on CoNi metal?organic framework (MOF) nanosheets on highly porous conductive graphene (PCG) is introduced for the hydrogen evolution reaction (HER). The electrocatalyst was fabricated by template-assisted chemical vapor deposition of graphene followed by solvothermal growth of CoNi-MOF nanosheets. Highly porous 3D structure of PCG with open channels of 200?500 nm sizes provided high active surface area and facilitates gas evolution. In a highly alkaline solution, the electrocatalyst exhibits superior figures of merits, e.g. overpotential of 265 mV at -10 mA cm-2 and Tafel slope of 44.5 mV dec-1, to existing hydrogen electrocatalysts. The resulting electrocatalyst exhibits the synergetic effect of CoNi-MOF and electroactive catalytic surface area of PCG on promoting the outstanding electrocatalytic performance. Electrochemical impedance spectroscopy evidenced high diffusion rate and fast charge transfer capability of CoNi-MOF-PCG electrode. This study opens up new possibility for design and fabrication of highly efficient bimetallic electrocatalysts for water splitting applications.

Automated summary

A highly efficient, cost-effective, and durable electrocatalyst based on CoNi metal-organic framework nanosheets and highly porous conductive graphene is introduced for the hydrogen evolution reaction. The electrocatalyst shows superior electrocatalytic performance and opens up new possibilities for highly efficient bimetallic electrocatalysts in water splitting applications.