In-situ formation of supported Au nanoparticles in hierarchical yolk-shell CeO₂/mSiO₂ structures as highly reactive and sinter-resistant catalysts

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• 作者：Jiasheng Fang ; Yiwei Zhang ; ^{zhangchem@seu.edu.cn} ; Yuming Zhou ; ^{ymzhou@seu.edu.cn} ; Shuo Zhao ; Chao Zhang ; Hongxing Zhang ; Xiaoli Sheng
• 关键词：Yolk-shell ; Gold precursor ; Catalytic activity ; Sinter resistance ; 4-Nitrophenol
• 刊名：Journal of Colloid and Interface Science
• 出版年：2017
• 出版时间：15 February 2017
• 年：2017
• 卷：488
• 期：Complete
• 页码：196-206
• 全文大小：3806 K
• 卷排序：488

文摘

A novel strategy was described to construct Au-based yolk-shell SCVmS-Au nanocomposites (NCs), which combined the sol-gel template-assisted process for the assembly of hierarchical SCVmS NCs with modified CeO2/mSiO2 as yolks/shells, and the unique deposition-precipitation (DP) process mediated with Au(en)2Cl3 compounds for the synthesis of extremely stable supported Au nanoparticles (NPs). Characterization results indicated that the obtained SCVmS-Au NCs featured mesoporous silica shells, tunable interlayer voids, movable CeO2-modified cores and numerous sub-5 nm Au NPs. Notably, the Au(en)2Cl3 was employed as gold precursors to chemically modify into the modulated yolk-shell structure through the DP process and the subsequent low-temperature hydrogen reduction induced the in-situ formation of abundant supported Au NPs, bestowing these metal NPs with ultrafine grain size and outstanding sinter-resistant properties that endured harsh thermal conditions up to 750 °C. Benefiting from the structural advantages and enhanced synergy of CeO2-Au/mSiO2-Au yolks/shells, the SCVmS-Au was demonstrated as markedly efficient catalysts with superior activity and reusability in catalyzing the reduction of 4-nitrophenol to 4-aminophenol, and its pristine morphology still maintained after eight recycling tests.