Enhanced Formaldehyde Oxidation Performance of the Mesoporous TiO2(B)-Supported Pt Catalyst: The Role of Hydroxyls

Tongtong Wei; Xuejuan Zhao; Long Li; Lei Wang; Shenjie Lv; Lei Gao; Gaosong Yuan; Licheng Li

doi:10.1021/acsomega.2c02490

Enhanced Formaldehyde Oxidation Performance of the Mesoporous TiO₂(B)-Supported Pt Catalyst: The Role of Hydroxyls

ACS Omega. 2022 Jul 14;7(29):25491-25501. doi: 10.1021/acsomega.2c02490. eCollection 2022 Jul 26.

Authors

Tongtong Wei¹, Xuejuan Zhao², Long Li¹, Lei Wang¹, Shenjie Lv¹, Lei Gao³, Gaosong Yuan³, Licheng Li¹

Affiliations

¹ Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, P. R. China.
² School of Materials Science and Engineering, Nanjing Institute of Technology, Nanjing 211167, P. R. China.
³ Jiangsu Architectural Decoration Integrated Installation Engineering Technology Research Center, Nanjing Guohao Decoration & Installation Engineering Co., Ltd., Nanjing, 210012, P. R. China.

Abstract

As one of the crystal phases of titania, TiO₂(B) was first utilized as a catalyst carrier for the oxidation of formaldehyde (HCHO). The mesoporous TiO₂(B) loaded with Pt nanoparticles enhanced the HCHO oxidation reaction whose reaction rate was 4.5-8.4 times those of other crystalline TiO₂-supported Pt catalysts. Simultaneously, Pt/TiO₂(B) exhibited long-term stable HCHO oxidation performance. The structural characterization results showed that in comparison with Pt/anatase, Pt/TiO₂(B) had more abundant hydroxyls, facilitating increasing the content of oxygen species. Studies on the role of hydroxyls in HCHO oxidation of Pt/TiO₂(B) illustrated that synergistic involvement of terminally bound hydroxyls and bridging hydroxyls in HCHO oxidation accelerated the transformation from HCHO to formate via dioxymethylene. Moreover, hydroxyls could avoid the accumulation of excessive formate on Pt/TiO₂(B) and promote the rapid oxidation of CO. Accordingly, the hydroxyl groups could accelerate each substep of formaldehyde oxidation, which enabled Pt/TiO₂(B) to exhibit excellent formaldehyde oxidation performance.