Enhanced catalytic methane combustion over Co₃O₄ nanowire arrays by cation substitution

By using a simple hydrothermal method, large scale Co₃O₄ nanowire catalysts have been grown onto stainless steel mesh substrates to increase the catalyst utilization efficiency. To further enhance the catalytic activity, Mn species are doped into Co₃O₄ for the substitution of Co cations in the lattice to modify the activity of reactive sites. Detailed microstructure characterizations and catalytic performance evaluation have been carried out, and we found that this cation substitution strategy can significantly improve the catalytic properties of Co₃O₄ nanowires towards methane combustion at low temperature with appropriate amount of Mn species. On the other hand, further increase Mn concentration would result in drastically decrease of specific surface area of synthesized nanostructures and adverse effect on their catalytic activities. This study provides a feasible approach for scalable synthesis and rational optimization of nanotructured metal oxide catalysts applicable for various catalytic applications. (paper)