Synthesis and electrocatalytic properties for p-nitrophenol deduction of nano-scaled M3O4 (M=Fe, Co) products with different shapes.

Spinel-structured M3O4 (M=Fe, Co) samples with different shapes were synthesised mainly via a hydrothermal procedure. All Fe3O4 samples were prepared using a one-step process; however, all Co3O4 samples were synthesised via two-step paths, namely their precursors were prepared first then the resultant oxide products were obtained by calcining their precursors at a certain temperature. The samples were characterised by thermogravimetric analysis, X-ray diffraction, transmission electron microscopy, high-resolution electron microscopy and field-emission scanning electron microscopy measurements, respectively. The results showed that plate-, particle- and sphere-like Fe3O4 and sheet-, particle- and tube-like Co3O4 samples were obtained successfully. The electrocatalytic properties of the samples modified on a glassy carbon electrode were investigated, and the results indicated that Fe3O4 and Co3O4 samples with different shapes exhibited different enhanced electrocatalytic activity for p-nitrophenol reduction, and Fe3O4 and Co3O4 nanoparticles all showed the highest elctrocatalytic activity. [ABSTRACT FROM AUTHOR]