(603g) Copper-Phyllosilicate Core-Shell Nanocatalysts with Balanced Active Sites for Carbon-Oxygen Hydrogenolysis Reactions

Copper-Phyllosilicate Core-shell Nanocatalysts with Balanced Active Sites for Carbon-Oxygen Hydrogenolysis Reactions

Hairong Yue, Kui Ma, Wei Jiang, Siyang Tang, Changjun Liu, Shaojun Yuan and Bin Liang

Multi-phases Mass Transfer and Reaction Engineering Laboratory, College of Chemical Engineering,

Sichuan University, Chengdu, China

Email: hryue@scu.edu.cn

Abstract

Hydrogenolysis of carbon-oxygen (C–O) bonds (e.g., esters, ethers, furfural, and CO₂) has emerged as a versatile synthetic tool in organic methodology, as it could produce a variety of products (e.g., chemicals, fuels, and polymers). Copper-based catalysts have been intensively explored for hydrogenation reactions as the copper sites account for the selective hydrogenation of carbon-oxygen bonds and relatively inactive for the hydrogenolysis of carbon-carbon bonds. Work on understanding the active sites of copper catalysts for hydrogenation reactions indicted that both Cu⁰ and Cu⁺ species were crucial to the activity of Cu-based catalysts. However, researchers were not able to establish a relationship between activity and Cu⁰/Cu⁺ active species since the conventional Cu-based catalysts is the deactivation by metal particle growth and unstable surface Cu⁰ and Cu⁺ active species in the strong reductive H₂ and oxidizing carbon-oxygen atmosphere.

We renctly present on efficient approaches for fabrication of a series of copper-phyllosilicate core-shell nanocatalysts and nanoreactors with balanced and stable Cu⁰ and Cu⁺ active species. We chose the hydrogenation of dimethyl oxalate, ethylene cyclicarbonate and as probe reactions for a better understanding of properties of active sites and the structure-activity relationship. The results indicated a synergy between copper and the oxide components and the balanced surface Cu⁰ and Cu⁺ species can greatly improve the catalytic C-O hydrogenolysis performance of the catalysts. These nanocatalysts with balanced and stable Cu⁰ and Cu⁺ active species, confinement effect, intrinsic high surface of Cu⁰ and Cu⁺ and unique tunable tubular morphology, has potential applications in the high-temperature hydrogenation reactions.

Keywords: core-shell nanocatalysts, Hydrogenation reaction; copper catalyst

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