Atomically Dispersed Ru Species Induced by Strong Metal–Support Interaction for Electrochemical Methane Reforming

Abstract

During the high-temperature oxygen evolution reaction for CO₂ electrolysis in solid oxide electrolysis cells (SOECs), the key elementary process of O^2- transfer is restricted by the high anodic oxygen pressure thermodynamically, thus requiring a high external voltage [open-circuit voltage (OCV)] to drive the electrolysis reaction. Herein, electrochemical CH₄ reforming is introduced to the SOEC anode, which remarkably lowers the anodic oxygen pressure and OCV, finally reducing the energy demand from 3.12 to 0.11 kW h per cubic meter of CO. Meanwhile, atomically dispersed Ru species is anchored on the anode surface due to the strong metal-support interaction, which exhibits superior CH₄ reforming activity (90% of CO selectivity) and stability (300 h) to the infiltrated Ru nanoparticles and doped Ru species in the bulk lattice at 600 °C. This work proposes an efficient strategy to boost the SOEC performance thermodynamically and produce value-added chemicals at both the cathode and anode of SOEC simultaneously.