Controlling Growth of CuO Nanoparticles on CuFe₂O₄ Nanotubes and Their Adsorption Kinetics

CuO nanoparticles (NPs) were created in situ on the surface of one-dimensional (1D) CuFe₂O₄ nanotubes (NTs) by controlling the diffusion of precursors via a two-step synthesis. Fiber precursors were firstly prepared by a single spinneret electrospinning method. A subsequent heat-treatment made the removal of polymers from the precursor fibers. The controlling of molar ratio between Cu and Fe and heating temperature resulted in the morphology change of products. The part of Cu precursors reacted with the Fe precursor to form CuFe₂O₄ and excess part was diffused to the surface to create CuO NPs. And the density of these NPs could be changed by adjusting the molar ratios of Cu and Fe precursors. CuO NPs were uniformly distributed on the surface of tubular CuFe₂O₄ fibers using a Cu/Fe molar ratio of 0.65 at 500 °C. Diffusion, nucleation, and growth processes are crucial for the formation and dispersion of CuO NPs. The results of CR adsorption and CO catalytic oxidation indicate that a proper surface structure can play a decisive role in the adsorptive property of the material.