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Outer-sphere radical hydrogenation of olefins proceeds via stepwise hydrogen atom transfer (HAT) from transition metal hydride species to the substrate. Typical catalysts exhibit M-H bonds that are either too weak to efficiently activate H 2 or too strong to reduce unactivated olefins. This contribution evaluates an alternative approach, that starts from a square-planar cobalt(II) hydride complex. Photoactivation results in Co-H bond homolysis. The three-coordinate cobalt(I) photoproduct binds H 2 to give a dihydrogen complex, which is a strong hydrogen atom donor, enabling the stepwise hydrogenation of both styrenes and unactivated aliphatic olefins with H 2 via HAT., (© 2021 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

La 2 O 3 exhibits good performance for various catalytic applications, such as oxidative coupling of methane (OCM) and dry reforming of methane (DRM), during which coke formation may lead to the deactivation of catalysts. Typically, the reaction between CO 2 adsorbed on La 2 O 3 and coke is the rate-determining step of the coke elimination process. This paper describes the influence of Ce addition on the CO 2 adsorption and activation over La 2 O 3 . Combined with in situ and ex situ characterization and density functional theory (DFT) calculation, we show that Ce addition promotes the formation of bidentate carbonate on La 2 O 3 via tuning CO 2 adsorption energy. In addition, Ce addition adjusts the ratio of bidentate/monodentate carbonate, and affects the ratio of hexagonal/monoclinic La 2 O 2 CO 3 on the binary oxides. DRM is used as a probe reaction to examine the coke elimination performance of Ce-La binary oxide. It is found that when the Ce/La ratio reaches the optimal value (0.15), Ce-La binary oxide has the highest CO 2 adsorption energy and predominantly promotes the formation of bidentate carbonate, and hence possesses the highest basicity above 700 °C and finally exhibits the best coke elimination performance.