Atmospheric-pressure O2 plasma treatment of Au/TiO2 catalysts for CO oxidation

• DOI: 10.1016/j.cattod.2015.04.027
• Publication Date: 2015-06-06T01:03:39Z
• Authors: Shuo Zhang; Xiao-Song Li; Bin Zhu; Jing-Lin Liu; Xiaobing Zhu; Ai-Min Zhu; Ben W.-L. Jang
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract Atmospheric-pressure O 2 plasma generated by dielectric barrier discharge (DBD) is applied to treat Au/TiO 2 catalysts synthesized via the deposition–precipitation method for CO oxidation. The plasma-treated sample (S-P) presents a higher activity than the calcined one (S-C). To elucidate the plasma treatment effect, XPS, TEM/HRTEM, sub-ambient pulse CO chemisorption and in situ DRIFTS techniques were used for catalyst characterization. In comparison with S-C, TEM/HRTEM reveals that the S-P catalyst has small particle size and narrow size distribution; XPS and DRIFTS analyses indicate plentiful surface hydroxyl groups on S-P sample. Pulse CO chemisorption and in situ DRIFTS of CO adsorption show that significant increase of low-coordinated Au species has been achieved by the plasma treatment. The improved activity of S-P is ascribed to large amount of low-coordinated Au species and interface active sites as well as abundant surface hydroxyl groups.