Lattice Strained Ni-Co alloy as a High-Performance Catalyst for Catalytic Dry Reforming of Methane

Abstract

Dry reforming of methane (DRM) is an effective route to convert methane and carbon dioxide to syngas. Herein, we report an efficient nickel–cobalt bimetallic catalyst with an activity of 4.97 molCH4 molNi–1 s–1 at 800 °C. It is active at low temperature as well, and near-thermodynamic equilibrium conversion was achieved as low as 350 °C, with a high yield of H2 implying inhibition of side reactions: i.e., a reverse water-gas shift (RWGS) reaction. The formation of Ni-Co alloy during the reaction was observed, and its lattice contraction was revealed by HAADF-STEM and EXAFS experiments. The lattice-strained Ni-Co alloy has good CO2 dissociation ability, which is responsible for its superior catalytic performance. Its weak chemisorption with H2 results in inhibition of RWGS side reactions. This work is helpful in the design and development of other metal alloy materials with novel structures and/or electronic configurations for catalytic applications.