21:T4bf,Oxidative dehydrogenation of propane (ODHP) as an exothermic process is a promising method to produce propene (C₃H₆) with lower energy consumption in chemical industry. However, the selectivity of the C₃H₆ product is always poor because of overoxidation. Herein, the ODHP reaction into C₃H₆ on a model rutile(R)-TiO₂(110) surface at low temperature via photocatalysis has been realized successfully. The results illustrate that photocatalytic oxidative dehydrogenation of propane (C₃H₈) into C₃H₆ can occur efficiently on R-TiO₂(110) at 90 K via a stepwise manner, in which the initial C-H cleavage occurs via the hole coupled C-H bond cleavage pathway followed by a radical mediated C-H cleavage to the C₃H₆ product. An exceptional selectivity of ∼90% for C₃H₆ production is achieved at about 13% propane conversion. The mechanistic model constructed in this study not only advances our understanding of C-H bond activation but also provides a new pathway for highly selective ODHP into C₃H₆ under mild conditions.22:T46c,The direct dehydrogenation of hydrocarbons to olefins under mild conditions is an atom-economical but challenging route. Here, we have investigated photocatalytic ethylbenzene dehydrogenation into styrene on rutile(R)-TiO₂(110) using the temperature-programmed desorption (TPD) method. The results demonstrate that photocatalytic ethylbenzene dehydrogenation into styrene occurs on R-TiO₂(110) in a stepwise manner, in which the initial α-C-H bond cleavage occurs facilely under UV irradiation via a possible homolytic hydrogen atom transfer process and then is followed by the second C-H bond cleavage induced by either photocatalysis at ∼120 K or thermocatalysis at >400 K. With preadsorbed oxygen atoms to eliminate hydrogen atoms from ethylbenzene dehydrogenation and excess electrons on the surface, the yield of styrene is largely enhanced by about 4 times. The results not only demonstrate a photocatalytic route for ethylbenzene dehydrogenation into styrene on R-TiO₂(110) but also advance our understanding of the photocatalytic activation of the saturated C-H bond with TiO₂.23:T4d7,Oxidative dehydrogenation of ethane (C₂H₆, ODHE) is a promising approach to producing ethene (C₂H₄) 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 C₂H₄ has been achieved successfully on a model rutile(R)-TiO₂(110) surface with high selectivity. Initially, the C₂H₆ 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 C₂H₄ without another photo-generated hole. In addition, parts of the radicals rebound with diversified surface sites to produce C₂ 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 C₂H₆ conversion, but also provides new opportunities for realizing the ODHE with high C₂H₄ efficiency under mild conditions.

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