Photocatalytic ethane conversion on rutile TiO 2 (110): identifying the role of the ethyl radical.

Oxidative dehydrogenation of ethane (C 2 H 6 , ODHE) is a promising approach to producing ethene (C 2 H 4 ) in the chemical industry. However, the ODHE needs to be operated at a high temperature, and realizing the ODHE under mild conditions is still a big challenge. Herein, using photocatalytic ODHE to obtain C 2 H 4 has been achieved successfully on a model rutile(R)-TiO 2 (110) surface with high selectivity. Initially, the C 2 H 6 reacts with hole trapped O Ti - centers to produce ethyl radicals , which can be precisely detected by a sensitive TOF method, and then the majority of the radicals spontaneously dehydrogenate into C 2 H 4 without another photo-generated hole. In addition, parts of the radicals rebound with diversified surface sites to produce C 2 products via migration along the surface. The mechanistic model built in this work not only advances our knowledge of the C-H bond activation and low temperature C 2 H 6 conversion, but also provides new opportunities for realizing the ODHE with high C 2 H 4 efficiency under mild conditions.