A comparison of dry and wet condition CO oxidation activity of a supported silver catalyst at low temperature. Issue 8 (14th March 2023)

• Record Type: Journal Article
• Authors: Chatterjee, Maya; Hiyoshi, Norihito; Fukuda, Takashi; Mimura, Naoki
• Is Part Of: Sustainable energy & fuels. Volume 7:Issue 8(2023)
• Page Start: 1878
• Page End: 1892
• Publication Date: 2023-03-14
• Subjects: Renewable energy sources -- Periodicals; Fuel cells -- Periodicals; Electric batteries -- Periodicals; Electrochemistry -- Periodicals; 660.297
• DOI: 10.1039/d2se01641a
• Languages: English
• ISSNs: 2398-4902

Abstract

Abstract : Economizing low-temperature CO oxidation using Ag/TiO2 catalyst to achieve complete conversion with and without water vapor through the activation of CO, initiated by the highly abundant reducible oxidic-Ag species at the metal–oxide interface. Abstract : The rational design of a highly efficient and sustainable strategy to remove CO by oxidation at low temperature is extremely desirable and increasingly important to control air pollution, interconnected to human health. However, the development of an efficient and cost-saving catalyst confronts challenges to activity and stability. Here, we developed a series of less expensive Ag catalysts supported on industrially relevant TiO2 and systematically investigated the CO oxidation activity after the characterization of the catalyst using various techniques. First, morphological analyses suggested the presence of spherical Ag particles dispersed on crystalline TiO2, and spectroscopic studies confirmed the existence of the Ag-oxide species. Furthermore, the Ag/TiO2 catalyst displayed remarkable CO oxidation activity without any oxidation–reduction pretreatment or surface modifications (a general trend to improve the catalytic efficiency). Notably, 3 wt% Ag/TiO2 completely converted CO at 80 °C ( T 50% = 34.6 °C) with high productivity and a turnover frequency of 1.4 μmolCO −1 gAg −1 s −1 and 5.2 × 10 −4 s −1 at 20 °C, respectively. Interestingly, Ag/TiO2 retained its excellent catalytic performance even in the presence of water, which significantly enhanced its stability. Moreover, the effect of different support materials was also investigated. Finally, a correlation between the catalytic activity and structural characterization was derived via multi-technique analyses, which illustrated that the remarkable activity and high stability of the catalyst are reliant on the synergistic contribution of active reducible Ag-oxide species and the support material at the metal–support interface.