In-situ fabrication and catalytic performance of Co-Mn@CuO core-shell nanowires on copper meshes/foams

This work reports a facile calcination-soak approach for the large-scale growth of Co-Mn composite shell over the cores of copper mesh and foam resulting in Co-Mn@CuO nanowires. In the synthesis of Co-Mn@CuO core/shell structure, CuO nanowires were first formed on copper mesh through a facile calcination, followed by Co-Mn compounds (MnO2 and CoOOH or Co(OH)3) soaking to form a coat on the outer surface of CuO nanowires attributed to the redox reaction between MnO4− and Co2+, which were calcined in air to get the final Co-Mn oxide. The thickness of the Co-Mn oxide shell over CuO nanowire could be easily tuned by soaking duration. The prepared Co-Mn@CuO nanowires were applied as monolithic catalysts in plasma-catalytic oxidation of toluene and decomposition of ozone. The catalytic performance was enhanced to ~88% at 1.0 A and ~95% at 1.5 A with the filling of Co-Mn@CuO core/shell structure as monolith catalyst, which could be attributed to the synergistic effect of plasma and catalytic effect. Using Co-Mn@CuO, 95% ozone conversion was achieved at room temperature credited to the presence of mixed-valent manganese ions in the catalyst. Keywords: VOCs, Non-thermal plasma, Ozone, Monolith, Catalytic oxidation