High‐Index Faceted PdPtCu Ultrathin Nanorings Enable Highly Active and Stable Oxygen Reduction Electrocatalysis
High‐Index Faceted PdPtCu Ultrathin Nanorings Enable Highly Active and Stable Oxygen Reduction Electrocatalysis
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高指数多面 PdPtCu 超薄纳米环可实现高活性和稳定的氧还原电催化
DOI：
10.1002/smtd.202100154
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发表时间：
2021
期刊：
影响因子：
12.4
通讯作者：
Shaojun Guo
中科院分区：
文献类型：
--
作者：
Menggang Li;Fenyang Tian;Tianshu Lin;Lu Tao;Xin Guo;Yuguang Chao;Ziqi Guo;Qinghua Zhang;Lin Gu;Weiwei Yang;Yongsheng Yu;Shaojun Guo
超薄纳米片催化剂在催化氧还原反应（ORR）方面提供了巨大的潜力，但遇到了表面原子利用率的上限，从而提出了与进一步提高催化活性相关的挑战。本文报道了一种具有更多电催化活性位的PdPtCu纳米环，其目的是打破传统催化剂的活性上限。所制备的PdPtCu纳米环在外表面和内表面的边缘处具有丰富的高折射率刻面。该催化剂的电化学活性比表面积为92.2m2 g-1 PGM，远高于商品Pt/C催化剂。优化后的Pd 39 Pt 33 Cu 28/C催化剂在0.9 V（vs. RHE）下的比活度为2.39 mA cm-2，质量活度为1.97 A mg-1，具有更高的ORR活性，并且在30 000次循环内具有优异的上级耐久性。密度泛函理论计算表明，高指数晶面和合金化Cu原子可以优化氧吸附能，解释了增强的ORR活性。这项工作克服了亚纳米电催化剂的关键技术障碍，成功地将中空结构引入到纳米片中，预示着燃料电池中高性能ORR催化剂的令人兴奋的前景。
Ultrathin nanosheet catalysts deliver great potential in catalyzing the oxygen reduction reaction (ORR), but encounter the ceiling of the surface atomic utilizations, thus presenting a challenge associated with further boosting catalytic activity. Herein, a kind of PdPtCu ultrathin nanorings with increased numbers of electrocatalytically active sites is reported, with the purpose of breaking the activity ceiling of conventional catalysts. The as‐made PdPtCu nanorings possess abundant high‐index facets at the edge of both the exterior and interior surfaces. An ultrahigh electrochemical active surface area of 92.2 m2g–1PGMis achieved on this novel catalyst, much higher than that of the commercial Pt/C catalyst. The optimized Pd39Pt33Cu28/C shows a great enhanced ORR activity with a specific activity of 2.39 mA cm–2and a mass activity of 1.97 A mg–1PGMat 0.9 V (versus RHE), as well as superior durability within 30 000 cycles. Density function theory calculations reveal that the high‐index facets and alloying Cu atoms can optimize the oxygen adsorption energy, explaining the enhanced ORR activity. Overcoming a key technical barrier in sub‐nanometer electrocatalysts, this work successfully introduces the hollow structures into the ultrathin nanosheets, heralding the exciting prospects of high‐performance ORR catalysts in fuel cells.