DFT study on effect of hydrophilic modification of catalyst on oxidation efficiency of hydrogen gas
(2.State Key Laboratory of Chemical Engineering, School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai, China 200237)
【Abstract】Hydrophilic surface modification of the catalyst surface is a common regulation method, which has important influences on the catalytic activity, selectivity and stability of the catalyst. In this study, the hydrogen-oxygen catalytic system was used as the research object, and the adsorption of hydrogen and water on different hydrophilic surfaces was calculated by multiscale density function theory (DFT) under molecular level. Finally, the effect of adsorption on reactive rate was studied. The results showed that the adsorption amount of water increased with more hydrophilic surface while the adsorption amount of hydrogen decreased. In addition, increasing bulk water density enhanced the adsorption of hydrogen on the surface. The above results not only explained the influence of hydrophilicity on the catalytic activity of the catalyst, but also had helpful guiding for the adjustment and enhancement of the surface reaction process.
【Keywords】 hydrophilicity; density function theory; adsorption; surface reaction;
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