Solution inheritance of CoC 2 O 4 ·2H 2 O rods to nanoparticle-assembled Co 3 O 4 rods

Abstract

Abstract An inheritance strategy for fabricating nanoparticle-assembled Co 3 O 4 rods was reported with CoC 2 O 4 ·2H 2 O rods as self-template in aqueous solution. The substitution–oxidation process (CoC 2 O 4 ·2H 2 O → Co(OH) 2 → Co 3 O 4 ) was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT–IR). The amount of NaOH, crystal characters of Co(OH) 2 intermediates and growth time of Co 3 O 4 play important roles on the formation of the nanoparticle-assembled Co 3 O 4 rods. Trace residual CoC 2 O 4 ·2H 2 O is necessary for keeping Co 3 O 4 nanoparticles in rod-shaped assembly. Comparing with the Co 3 O 4 rods obtained by calcining CoC 2 O 4 ·2H 2 O rods at high temperature, the solution synthesized nanoparticle-assembled Co 3 O 4 rods performed higher activities on photocatalytic degradation of rhodamine B (RhB) and catalytic decomposition of ammonium perchlorate (AP).