Controlled Vacancy-Assisted C–C Couplings of Acetaldehyde on Rutile TiO2(110)

• Published in: Journal of physical chemistry. C Vol. 118; no. 48; pp. 27920 - 27924
• Main Authors: Yang, Wenshao, Geng, Zhenhua, Xu, Chenbiao, Guo, Qing, Dai, Dongxu, Yang, Xueming
• Format: Journal Article
• Language: English
• Published: American Chemical Society 04.12.2014
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp509091a

Reductive C–C coupling of acetaldehyde (CH3CHO) on rutile TiO2(110) surface with controlled oxygen vacancy coverage was investigated by temperature-programmed desorption (TPD). Two main reaction products, 2-butanone and butene, have been detected. Experimental results suggest that the two products are produced via two distinctive vacancy-assisted C–C couplings on the surface. The 2-butanone product is produced via the reductive C–C coupling of CH3CHO on reduced rutile TiO2(110) in which one CH3CHO molecule adsorbed on the five coordinated Ti site (Ti5c) and the other on a nearby bridge-bonded oxygen (BBO) vacancy site; while butene is produced from the self-coupling of two CH3CHO molecules adsorbed on two adjacent BBO vacancy sites. The results of this work indicate that surface vacancy plays a key role in the C–C coupling reactions of CH3CHO.