Luke Roebuck, Helen Daly, Lan Lan, Joseph Parker, Angus Gostick, Nathan Skillen, Sarah J. Haigh, Marta Falkowska, Christopher Hardacre
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引用次数: 0
Abstract
In this work, the mechanism of H2 production from ethylene glycol as a model compound for photoreforming over platinized TiO2 is presented with particular focus on the effect of the TiO2 polymorph. It was found that Pt/anatase and Pt/anatase:rutile (P25) had similar H2 production activities and both catalysts followed an indirect oxidation pathway where ethylene glycol was oxidised via hydroxyl radicals to glycolaldehyde. In contrast, Pt/rutile primarily oxidised ethylene glycol directly into formaldehyde. The formaldehyde was unable to react further, which significantly reduced the formation of hydrogen despite similar conversion of ethylene glycol compared with the other supports used. We propose that these differences are due to different adsorption behaviour and hole transfer mechanism on the different TiO2 crystalline phases. In particular, ethylene glycol complexation on Ti5c sites on the dominant (110) facet of rutile leads to a direct hole transfer and an oxidative C–C cleavage mechanism prevailing.
期刊介绍:
The Journal of Catalysis publishes scholarly articles on both heterogeneous and homogeneous catalysis, covering a wide range of chemical transformations. These include various types of catalysis, such as those mediated by photons, plasmons, and electrons. The focus of the studies is to understand the relationship between catalytic function and the underlying chemical properties of surfaces and metal complexes.
The articles in the journal offer innovative concepts and explore the synthesis and kinetics of inorganic solids and homogeneous complexes. Furthermore, they discuss spectroscopic techniques for characterizing catalysts, investigate the interaction of probes and reacting species with catalysts, and employ theoretical methods.
The research presented in the journal should have direct relevance to the field of catalytic processes, addressing either fundamental aspects or applications of catalysis.