Efficient catalyst of defective CeO2-x and few-layer carbon hybrid for oxygen reduction reaction
Efficient catalyst of defective CeO2-x and few-layer carbon hybrid for oxygen reduction reaction
复制标题
有缺陷的CeO2·x和少层碳杂化物用于氧还原反应的高效催化剂
DOI：
10.1016/j.jallcom.2016.07.060
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发表时间：
2016-12-15
影响因子：
6.2
通讯作者：
Huang, Fuqiang
中科院分区：
文献类型：
--
作者：
Yuan, Xiaotao;Ge, Hongxin;Huang, Fuqiang
CeO2纳米材料作为优良的催化剂广泛应用于CO氧化、尾气净化和气体重整等领域，但在氧还原反应（ORR）中的应用却很少。在此，提出了一种通过直流电弧放电工艺制备的少层碳封装的富含缺陷的CeO2-x（CeO2-x@C）的混合物，作为一种新型高效的ORR催化剂。 CeO2-x 的缺陷结构，包括氧空位和 Ce3+ 的存在，对 ORR 催化起着重要作用。与无缺陷的CeO2-碳杂化物相比，我们的CeO2-x@C实现了更高的正起始电位（类似于0.74 V）、更大的极限电流密度（类似于6 mA cm(-2)）和类似于4的电子转移数。与通过水热法制备的样品相比，电弧放电工艺制备的CeO2-x具有更均匀的结构和无表面活性剂的表面，这也可能有助于高ORR活性。除了良好的 ORR 活性外，我们的 CeO2-x@C 还表现出优异的稳定性和良好的抗甲醇交叉效应。 (C) 2016 年由 Elsevier B.V. 出版
CeO2 nanomaterials are widely used as excellent catalysts for CO oxidation, tail gas purification and gas reforming, but they are rarely used in the oxygen reduction reaction (ORR). Here, a hybrid of few-layer carbon encapsulated defect-rich CeO2-x (CeO2-x@C), which was prepared by an direct-current arc-discharge process, is presented as a new efficient ORR catalyst. The defective structure of CeO2-x, involving oxygen vacancies and the presence of Ce3+, plays an important role on the ORR catalysis. Our CeO2-x@C achieves more positive onset potential (similar to 0.74 V), larger limited current density (similar to 6 mA cm(-2)) and an electron transfer number of similar to 4, compared to the non-defective CeO2-carbon hybrid. Compared to the sample prepared via hydrothermal method, the CeO2-x derived from arc-discharge process has more uniform structure with surfactant-free surface, which may also contribute to the high ORR activity. Besides good ORR activity, our CeO2-x@C also shows excellent stability and good resistance to methanol crossover effects. (C) 2016 Published by Elsevier B.V.