Green and facile synthesis of nanostructured Co3O4/CeO2 catalysts via a glucose-urea method for NO oxidation

Abstract

Nanocatalysis plays an important role in chemical industrial production, environmental protection and etc. However, traditional catalyst preparation methods are generally labor-intensive, time-consuming and need high-temperature calcination, which are not conducive to the preparation of nanostructured catalyst. Therefore, developing a green and facile method for nano-sized catalyst preparation is very significative. In this work, a series of nano-sized Co3O4/CeO2 catalysts with high specific surface area, high oxygen storage and homogeneous distribution of active species were synthesized via a glucose-urea (G-U method), and applied in NO oxidation The NO oxidation performance indicates that the 12.5% CoCeG−U catalyst prepared by the G-U method shows higher activity than those of catalysts prepared by the traditional methods (precipitation, hydrothermal and impregnation methods). The characterization results revealed that the CoCeG−U catalysts have the highest specific surface area, pore volume, content of surface Ce3+ and Co3+ among the catalysts. Moreover, the nano Co3O4 is better dispersed on CeO2, which resulted in more active oxygen species on the surface of the catalysts prepared by the G-U method. Herein, the higher specific surface area, the smaller Co3O4 nanoparticles, the more active oxygen species and the higher Ce3+ and Co3+ contents of the CoCeG−U catalyst lead to the more excellent NO oxidation performance. This work provides a green and efficient approach for the industrial production of nano-sized oxide catalysts.