A facile template method to fabricate strongly coupled 1D sandwich-like C@Fe3O4@C/Ni coaxial microtubes with enhanced catalytic performance

Abstract

The development of low-cost non-noble metal catalysts with high activity and good durability is critical for catalysis applications. However, the poor dispersity and oxidation resistance of nickel nanoparticles (NPs) often lead to a poor performance in catalytic applications, which then significantly limits further applications of this kind of material. In this work, sandwich-like C@Fe₃O₄@C/Ni microtubes are constructed in situ, in which tiny Ni NPs are densely embedded in an outer carbon layer derived from a resorcinol–formaldehyde (RF) polymer while an inner carbon layer from polypyrrole (PPy) microtubes supports the Fe₃O₄ NPs. The peculiar tubular shape of the carbon microtubes favors the dispersion and surface availability of the supported Ni NPs which are active in the catalytic pathway. Moreover, by virtue of the synergistic effects of these sandwich-like structures, the metallic Ni NPs and the inner Fe₃O₄ layer, the C@Fe₃O₄@C/Ni microtubes manifested an excellent catalytic performance and recycling ability in the reduction of 4-nitrophenol.