Boosting Toluene Combustion by Engineering Co–O Strength in Cobalt Oxide Catalysts

Abstract

Exploring active and low-cost transition metal oxides (TMOs) based catalysts for volatile organic compounds (VOCs) abatement is vital for air pollution control technologies. Since 18 oxygen atoms are required for the complete mineralization of a toluene molecule, the participation of a large amount of active oxygen is a key requirement for the catalytic oxidation of toluene. Here, toluene degradation was improved by weakening the Co–O bond strength on the surface of cobalt oxide, so as to increase the amount of active oxygen species, while maintaining the high stability of the catalyst for toluene combustion. The bond strength of Co–O and the amount of surface active O2 was regulated by tuning the pyrolysis temperature. The catalyst’s redox ability and surface oxygen species activity are improved due to the weakening of the Co–O bond strength. It has been demonstrated that active oxygen plays a crucial role in boosting toluene combustion by engineering Co–O strength in cobalt oxide catalysts. This work provides a new understanding of the exploration and development of high-performance TMO catalysts for VOCs abatement.

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

“…5a, correspond to the lattice O 2 (O latt ) and chemisorbed O 2 (O ads ). 23,26,27 Importantly, the O latt and O ads species in the CuO/Co 3 O 4 catalysts exhibited a negative shift (0.2 eV), which implied that those samples possess more oxygen vacancies, thus increasing the electron density of the oxygen groups. 23 The lower binding energies of the oxygen species in the CuO/ Environmental Science: Nano Paper Co 3 O 4 sample also implied the relatively easy activation of molecular oxygen.…”

“…17,18 One of the more promising candidates of the transition metal-based catalysts is spinel Co 3 O 4 , which has exhibited high chemical/thermal stability and good catalytic capacity. [19][20][21] A study conducted by Ren et al 20 showed that three-dimensional Co 3 O 4 microspheres with plenty of surface-adsorbed O 2 groups and a high ratio of Co 3+ species could effectively remove toluene at a low temperature and remain stable during the on-stream test for over 120 h. The catalytic performance of Co 3 O 4 was affected by factors such as the types of precipitation agents, 22 Co-O bond strength, 23 and N-doping. 24 Although highly promising to be used as an alternative for noble metalsupported catalysts, the catalytic performance of Co 3 O 4 needs to be improved to satisfy the highly demanding industrial applications.…”

Investigation into the Phase–Activity Relationship of MnO2 Nanomaterials toward Ozone‐Assisted Catalytic Oxidation of Toluene

“…Toluene, one of the representatives of volatile organic compounds (VOCs), is considered as a major air pollutant threatening human health, owing to its serious teratogenicity and carcinogenicity. [ 1–3 ] At present, many strategies have been developed to control toluene, including biodegradation, [ 4,5 ] plasma technology, [ 6–8 ] photocatalytic oxidation, [ 2,9–15 ] thermal catalytic oxidation, [ 16–18 ] and the latest rising ozone‐assisted catalytic oxidation. [ 19–26 ] Ozone‐assisted catalytic oxidation is considered as a promising way, owing to its mild reaction condition, for simple craft and low energy consumption.…”

Efficient catalytic combustion of toluene at low temperature by tailoring surficial Pt0 and interfacial Pt-Al(OH)x species

“…The above results implied that the existence of Al-O-Pt interfaces in the Pt/γ-Al 2 O 3 catalysts. Meanwhile, the elongation of the Pt–O bond also facilitated the activation of the surface oxygen ( Shen et al., 2020 ).

Figure 3 Chemical properties of Pt species (A and B) (A) Normalized XANES spectra at the Pt L 3 -edge of Pt foil, PtO 2 and the as-prepared catalysts, (B) magnitude of the Fourier transform (FT) k 3 -weight EXAFS data for for Pt and as-prepared catalysts (dash line: fit of the experimental data), see also Figure S7 Table S3 .

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