Mesostructured cellular foam silica supported Au-Pt nanoalloy: Enrichment of D-state electrons for promoting the catalytic synergy
Mesostructured cellular foam silica supported Au-Pt nanoalloy: Enrichment of D-state electrons for promoting the catalytic synergy
复制标题
介孔结构多孔泡沫二氧化硅负载 Au-Pt 纳米合金：富集 D 态电子以促进催化协同作用
DOI：
10.1016/j.micromeso.2021.110982
复制
发表时间：
2021
影响因子：
5.2
通讯作者：
Yan Zifeng
中科院分区：
文献类型：
--
作者：
Wu Pingping;Liu Haijun;Cao Yunxiang;Xi Shibo;Li Zhiheng;He Zhengke;Song Lei;Xu Jing;Bai Peng;Zhao Lianming;Mintova Svetlana;Yan Zifeng
采用介孔泡沫（MCF）二氧化硅负载金（Au）-铂（Pt）合金纳米粒子（NPs），用于苯甲醇的部分氧化.研究表明，金（Au）-铂（Pt）纳米颗粒（NP）催化剂具有催化协同效应，即在Pt中引入Au后，催化性能提高。然而，这种协同效应的本质仍在争论中。本文设计了一系列MCF负载的Au-Pt NP催化剂，揭示了其本质，MCF载体发达的多孔结构消除了传质限制，获得了本征催化活性。Au-Pt合金纳米粒子的形成使催化剂活性中心的几何结构和电子结构发生了变化，从而提高了催化剂的催化性能。与单金属催化剂相比，金铂合金的形成导致了催化剂颗粒尺寸和晶格结构的变化。电子性质分析证实，Au-Pt合金纳米粒子上d态电子的增加（由s-p-d杂化和原子内电荷重新分布计算）导致费米能级附近可转移d电子丰度的增加，进一步提高了催化活性。这些发现获得了新的见解的催化协同作用的纳米粒子，并阐明了这些催化剂的优化。
A mesostructured cellular foam (MCF) silica was applied to support gold (Au) – platinum (Pt) alloy nanoparticles (NPs) for benzyl alcohol partial oxidation. A catalytic synergy on bimetallic gold (Au)-platinum (Pt) nanoparticle (NP) catalyst, referring to that introducing Au to Pt leading to a higher catalytic performance has been observed. However, the essence of this synergistic effect is still under debate. In this work, a series of MCF supported Au–Pt NP catalysts are designed to reveal the essence.Well-developed porous structure of MCF support eliminated the mass transfer limitation and intrinsic catalytic activity was obtained. The improved catalytic performance on bimetallic catalyst is attributed to the geometric and electronic changes of active sites after formation of Au–Pt alloy NPs. Compared with monometallic catalyst, the formation of Au–Pt alloy results in the changes of particle size and lattice structure. Electronic property analyses confirmed the increase of d state electrons on Au–Pt alloy NPs, which are calculated from s-p-d hybridization and intra-atomic charge redistribution, leading to the increased abundance of transferable d electrons near Fermi level and further enhancing the catalytic activity. These findings gain new insights into the catalytic synergy of bimetallic nanoparticles and shed light on the optimization of these catalysts.