Smart tuning of 3D ordered electrocatalysts for enhanced oxygen reduction reaction
Smart tuning of 3D ordered electrocatalysts for enhanced oxygen reduction reaction
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DOI：
10.1016/j.apcatb.2017.08.017
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发表时间：
2017-12
影响因子：
22.1
通讯作者：
Yi-fei Sun;Yaqian Zhang;Yan-Ling Yang;Jian Chen;B. Hua;Yixiang Shi;Chang‐an Wang;Jingli Luo
中科院分区：
文献类型：
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作者：
Yi-fei Sun;Yaqian Zhang;Yan-Ling Yang;Jian Chen;B. Hua;Yixiang Shi;Chang‐an Wang;Jingli Luo
广泛的研究致力于开发具有功能多样的活性位点的高级氧还原反应（ORR）催化剂。在本文中，我们展示了一种智能方法来提高3D多孔钙钛矿的ORR催化活性。对Ag掺杂的LaFeO 3进行简单的氧化-还原-氧化（O-R-O）热处理循环可以逐步切换到三个不同的反应位点（析出的Ag-NPs、氧缺陷和具有最佳电子构型的Fe 4+）进行ORR。详细的表征表明，ORR活性基本上来源于分级多孔支架，其提供了大的表面积和足够的孔体积用于质量和离子扩散。更重要的是，三种不同类型的反应位点之间的独特协同效应赋予了氧气吸附，活化和O2−运输的速度。举例说明的结果提出了新的设计原则，优化替代催化剂。
Extensive research has been devoted to the development of advanced oxygen reduction reaction (ORR) catalysts with functionally diverse active sites. Herein, we show a smart approach to advancing the ORR catalytic activity of a 3D porous perovskite. The facile oxidative-reductive-oxidative (O-R-O) thermal treatment cycle executed on Ag doped LaFeO3could stepwise switch on three different reaction sites (exsolved Ag-NPs, oxygen deficiency and Fe4+with optimal electron configuration) for ORR. Detailed characterizations illustrate that the ORR activity is basically derived from the hierarchically porous scaffold which provides a large surface area and enough pore volumes for mass and ion diffusion. More importantly, the unique synergistic effects among three separate kinds of reaction sites endow the speed-up of oxygen adsorption, activation and O2−transportation. The exemplified results set out new design principles for the optimization of alternative catalysts.