Hollow Multishelled Structure of Heterogeneous Co₃O₄–CeO₂₋<i>_x</i> Nanocomposite for CO Catalytic Oxidation

Abstract Herein, hollow multishelled structure (HoMS) of Co 3 O 4 –CeO 2− x nanocomposites with controllable molar ratio of Co and Ce elements is synthesized by a general strategy sequential templating approach (STA) with a facile and efficient electrostatic spray process. As a catalyst of carbon monoxide (CO) catalytic oxidation, Co 3 O 4 –CeO 2− x (Co/Ce = 4/1) HoMS achieves good catalytic activity (complete conversion temperature is 166.9 °C) and stability (100 h). This performance is attributed to synergistic effects between the two components. The combination of Co 3 O 4 and CeO 2 not only generates more interfaces of Co 3 O 4 –CeO 2− x , which is more favorable for the activation of oxygen, but also improves the oxidizability of Co 3 O 4 as well as the capacity of oxygen storage of CeO 2 . In addition, the relatively larger effective specific surface area of the HoMS can provide more active sites, while the unique structure of HoMS can facilitate gas diffusion and maintain structural stability.