Zeolitic Imidazolate Framework-67-Derived CeO₂@Co₃O₄ Core–Shell Microspheres with Enhanced Catalytic Activity toward Toluene Oxidation

Abstract

In this work, a core–shell structured CeO2@Co3O4 catalyst was successfully prepared by using a zeolitic imidazolate framework-based material as a sacrificial template. The structure, morphology, and physicochemical characteristics of these materials were investigated by X-ray diffraction, N2 sorption, Fourier transform infrared spectroscopy, Raman spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, temperature-programmed desorption, and temperature-programmed reduction studies. Compared with pure Co3O4 and CeO2, the CeO2@Co3O4 sample displayed superior catalytic performance (T 90 = 225 °C) toward toluene oxidation. Results demonstrated that the CeO2@Co3O4 sample exhibited a core–shell structure, with hierarchically wrinkled surfaces. This unique structure, especially the interface between the core and the shell, endowed the CeO2@Co3O4 catalyst with better activity. In addition, there was a synergistic effect between cerium and cobalt oxides in the core–shell bimetallic sample, which was responsible for the improved performance of the material. Moreover, surface-active oxygen species involved and played a significant role in toluene oxidation.

Interfacial effects in CuO/Co3O4 heterostructures enhance benzene catalytic oxidation performance

“…H 2 O and CO 2 ) at a relatively low temperature and the convenience of remote operation. [8][9][10] Currently, the major challenge of catalytic combustion lies in the rational design and synthesis of catalysts with satisfactory catalytic activity and stability. [11][12][13] Precious metal-supported catalysts demonstrate overall better catalytic combustion performance for VOCs than other types of catalysts, but their application is largely hindered by the associated costs.…”

Enhanced Catalytic Combustion Performance of Toluene over a Novel Co–CeOx Monolith Catalyst

“…Although we can hardly compare under the same conditions, it can be observed that the catalyst Co 1 Ce 2 O x has comparative performance advantages in toluene oxidation. The as-synthesized catalyst Co 1 Ce 2 O x presents catalytic performance superior to catalysts CuO/CeO 2 –ZrO 2 , comparable to core–shell CeO 2 @Co 3 O 4 catalysts and MnO x /CeO 2 –ZrO 2 to a certain degree.…”

“…Additionally, a comparison of catalytic activities between the recently published results and this as-prepared optimal catalyst Co 1 Ce 2 O x in the catalytic combustion of toluene was given. − As is shown in Table S1, because the monolithic catalyst we adopted is obviously different from the catalyst structure reported in the literature (mainly in the form of powder), we need to take catalyst mass, reaction gas composition, and reaction gas flow rate into consideration to compare the performance. Although we can hardly compare under the same conditions, it can be observed that the catalyst Co 1 Ce 2 O x has comparative performance advantages in toluene oxidation.…”

Low-Temperature Oxidation of Toluene over MnOx–CeO2 Nanorod Composites with High Sinter Resistance: Dual Effect of Synergistic Interaction on Hydrocarbon Adsorption and Oxygen Activation

“…Based on pure CeO 2 , introducing additional components like noble metals or non-noble metal oxides becomes another strategy to achieve better catalytic performance in VOC degradation . Peng et al found that when Pt was loaded on cerium oxide carriers with different morphologies (nanorods, nanoparticles, and nanocubes), the catalysts with nanorod as a carrier exhibited much better performance in catalytic toluene oxidation.…”