Highly efficient electrochemical reforming of CH₄/CO₂ in a solid oxide electrolyser.

Abstract

Reforming CH₄ into syngas using CO₂ remains a fundamental challenge due to carbon deposition and nanocatalyst instability. We, for the first time, demonstrate highly efficient electrochemical reforming of CH₄/CO₂ to produce syngas in a solid oxide electrolyser with CO₂ electrolysis in the cathode and CH₄ oxidation in the anode. In situ exsolution of an anchored metal/oxide interface on perovskite electrode delivers remarkably enhanced coking resistance and catalyst stability. In situ Fourier transform infrared characterizations combined with first principle calculations disclose the interface activation of CO₂ at a transition state between a CO₂ molecule and a carbonate ion. Carbon removal at the interfaces is highly favorable with electrochemically provided oxygen species, even in the presence of H₂ or H₂O. This novel strategy provides optimal performance with no obvious degradation after 300 hours of high-temperature operation and 10 redox cycles, suggesting a reliable process for conversion of CH₄ into syngas using CO₂.