Co3O4‑Impregnated NiO–YSZ: An Efficient Catalyst for Direct Methane Electrooxidation

• Published in: ACS applied materials & interfaces Vol. 12; no. 29; pp. 32578 - 32590
• Main Authors: Shahid, Mohamed, He, Cheng, Sankarasubramanian, Shrihari, Ramani, Vijay K, Basu, Suddhasatwa
• Format: Journal Article
• Language: English
• Published: American Chemical Society 22.07.2020
• Subjects: Energy, Environmental, and Catalysis Applications; solid oxide fuel cell; impregnated anode and temperature-programmed reduction; coking; strong metal−support interaction
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.0c06407

Co3O4-impregnated NiO–YSZ (yttria-stabilized zirconia) is a possible electrocatalyst for direct methane electrooxidation with both high catalytic activity and the ability to mitigate coking. The physical and electrochemical properties of Co3O4-impregnated NiO–YSZ anodes are investigated and benchmarked against NiO–YSZ and CeO2-impregnated NiO–YSZ anodes. The following methane electrooxidation activity trend: Co3O4-impregnated NiO–YSZ > CeO2-impregnated NiO–YSZ > NiO–YSZ with i o (exchange current density) values of 88, 83, and 2 mA cm–2, respectively, is obtained in the high overpotential region. The high activity of Co3O4-impregnated NiO–YSZ is attributed to the changes in the electronic structure and microstructure with the incorporation of nickel into the lattice of Co3O4 as observed using X-ray photoelectron spectroscopy, temperature-programmed reduction, high-resolution transmission electron microscopy, and field emission scanning electron microscopy. Co3O4-impregnated NiO–YSZ also demonstrated the least coking during operation, confirming its utility as a methane electrooxidation catalyst.