Hydrothermal Synthesis of Co3O4 Urchin-Like and their Catalytic Properties in Co Oxidation

Abstract

Urchin-like nanocrystalline Co 3 O 4 has been success fully prepared through a hydrothermal synthesis route via a simple and elegant route at low temperature, and was characterized by thermal analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, nitrogen adsorption/desorption isotherms and X-ray photoelectron spectroscopy (XPS). The light-off temperature (10% conversion) of CO oxidation on Co 3 O 4 ursin-like catalyst was at 60°C and when the temperature reaches 120°C, the CO conversion ratio reaches 100%. The high relative concentration surface-adsorbed oxygen on the Co 3 O 4 ursin-like is highly active in CO oxidation reaction due to its higher mobility than lattice oxygen. The study it has been shown that the high catalytic activity and stability for CO oxidation can be attributed to its higher mobility than lattice oxygen. In addition, the oxide defects can adsorb and activate gaseous O2 to form active oxygen species, which is beneficial to promote the CO oxidation reaction. The as-obtained results make the Co 3 O 4 nanomaterial possible candidate to be used as catalyst for CO oxidation.