Synthesis and Characterization of Pt‐Ag Icosahedral Nanocages with Enhanced Catalytic Activity toward Oxygen Reduction
Synthesis and Characterization of Pt‐Ag Icosahedral Nanocages with Enhanced Catalytic Activity toward Oxygen Reduction
复制标题
具有增强氧还原催化活性的 Pt-Ag 二十面体纳米笼的合成与表征
DOI：
10.1002/cnma.202200186
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发表时间：
2022
期刊：
影响因子：
3.8
通讯作者：
Xia, Younan
中科院分区：
文献类型：
--
作者：
Wang, Wenxia;Shi, Yifeng;Chen, Zitao;Zhao, Ming;Cao, Zhenming;Lyu, Zhiheng;Chen, Ruhui;Xiao, Kaijun;Chi, Miaofang;Xia, Younan
迫切需要开发基于Pt的具有成本效益的电催化剂，用于广泛的应用，包括对燃料电池运行至关重要的应用。挖空Pt纳米晶体的内部提供了一种简单可行的策略，用于最大化这种贵金属的利用效率，同时增强电催化性能。在这里，我们报告的合成和电催化评价的Pt−Ag二十面体纳米笼的平均壁厚为1.6 nm。 Pt原子被包覆在Ag二十面体晶种的表面上，导致形成具有可调壳厚度的Ag@ PtnL核-壳二十面体纳米晶体。然后通过选择性地蚀刻掉核中的Ag将核-壳纳米晶体转化为二十面体纳米笼。所获得的具有Pt4.5Ag组成的纳米笼在酸性介质中相对于商业Pt/C表现出几乎3倍的对氧还原的比活性增强。
There is an urgent need to develop cost‐effective electrocatalysts based on Pt for a broad spectrum of applications, including those vital to the operation of fuel cells. Hollowing out the interior of Pt nanocrystals offers a simple and viable strategy for maximizing the utilization efficiency of this precious metal while enhancing the electrocatalytic performance. Herein, we report the synthesis and electrocatalytic evaluation of Pt−Ag icosahedral nanocages with an average wall thickness of 1.6 nm. The Pt atoms are coated on the surface of Ag icosahedral seeds, leading to the formation of Ag@PtnLcore‐shell icosahedral nanocrystals with tunable shell thicknesses. The core‐shell nanocrystals are then converted to icosahedral nanocages by selectively etching away the Ag in the core. The as‐obtained nanocages with a composition of Pt4.5Ag exhibit an almost 3‐fold enhancement in specific activity toward oxygen reduction relative to the commercial Pt/C in acid media.