Integrating Catalysis of Methane Decomposition and Electrocatalytic Hydrogen Evolution with Ni/CeO for Improved Hydrogen Production Efficiency.

Ni/CeO enables either methane decomposition or water electrolysis for pure hydrogen production. Ni/CeO , prepared by a sol-gel method with only one heat treatment step, was used to catalyze methane decomposition for the generation of H . The solid byproduct, Ni/CeO /carbon nanotube (CNT), was further employed as an electrocatalyst in the hydrogen evolution reaction (HER) for H production. The Ni/CeO catalyst exhibits excellent activity for methane decomposition because CeO prevents carbon encapsulation of Ni nanoparticles during the preparation process and forms a special metal-support interface with Ni. The derived CNTs act as antenna to improve conductivity and promote the dispersion of agglomerated Ni/CeO . In addition, they provide H diffusion paths and prevent Ni/CeO from peeling off the HER electrode. Although long-term methane decomposition reduces the HER activity of Ni/CeO /CNTs (owing to degradation of the delicate Ni/CeO interface), the tunable nature of the synthesis makes this an attractive sustainable approach to synthesize future high-performance materials.