Yang Fan, Wu Chunzheng, Yu Hongbo, Wang Shiwei, Li Tong, Yan Bo, Yin Hongfeng
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 1219 Zhongguan West Road, Ningbo, Zhejiang 315201, P. R. China.
Nanoscale. 2021 Apr 14;13(14):6856-6862. doi: 10.1039/d1nr00173f. Epub 2021 Mar 26.
Nanosized Au catalysts suffer from serious sintering problems during synthesis or catalytic reactions at high temperatures. In this work, we integrate dumbbell-shaped Au-FeO heterostructures into hollow ZrO nanocages to make Au-FeO@ZrO yolk-shell nanoreactors with high activity as well as ultra-high sintering resistance for high-temperature CO oxidation. The synthesis starts with the fabrication of a (Au-FeO)@SiO@ZrO core-shell nanostructure with a Au-FeO dumbbell nanoparticle (DB) core and SiO/ZrO double shells, followed by calcination and the selective removal of the inner SiO shell with alkaline solution to obtain Au-FeO@ZrO nanoreactors. The retained ZrO hollow (outer) shells protect the Au NPs from aggregation at temperatures up to 900 °C and show excellent long-term stability. Compared to Au@ZrO yolk-shell nanoreactors, Au-FeO@ZrO shows improved activity in CO oxidation due to the active Au-FeO interface. This strategy can be extended to other yolk-shell nanoreactors with various nanocomposites and for different catalytic reactions.
纳米尺寸的金催化剂在合成过程中或高温催化反应中存在严重的烧结问题。在这项工作中，我们将哑铃状的金-氧化铁异质结构整合到中空的氧化锆纳米笼中，制成具有高活性以及对高温一氧化碳氧化具有超高抗烧结性的金-氧化铁@氧化锆蛋黄壳纳米反应器。合成过程首先是制备具有金-氧化铁哑铃形纳米颗粒（DB）核和二氧化硅/氧化锆双层壳的（金-氧化铁）@二氧化硅@氧化锆核壳纳米结构，然后进行煅烧，并用碱性溶液选择性去除内部的二氧化硅壳，从而获得金-氧化铁@氧化锆纳米反应器。保留的氧化锆中空（外部）壳在高达900℃的温度下保护金纳米颗粒不发生聚集，并表现出优异的长期稳定性。与金@氧化锆蛋黄壳纳米反应器相比，由于活性金-氧化铁界面，金-氧化铁@氧化锆在一氧化碳氧化中表现出更高的活性。这种策略可以扩展到其他具有各种纳米复合材料的蛋黄壳纳米反应器以及不同的催化反应。
