Strongly Coupled Pd Nanotetrahedron/Tungsten Oxide Nanosheet Hybrids with Enhanced Catalytic Activity and Stability as Oxygen Reduction Electrocatalysts

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• 作者：Yizhong Lu ; Yuanyuan Jiang ; Xiaohui Gao ; Xiaodan Wang ; Wei Chen
• 刊名：Journal of the American Chemical Society
• 出版年：2014
• 出版时间：August 20, 2014
• 年：2014
• 卷：136
• 期：33
• 页码：11687-11697
• 全文大小：772K
• ISSN：1520-5126

文摘

The design and synthesis of highly active oxygen reduction reaction (ORR) catalysts with strong durability at low cost is extremely desirable but still remains a significant challenge. Here we develop an efficient strategy that utilizes organopalladium(I) complexes containing palladium鈥損alladium bonds as precursors for the synthesis of strongly coupled Pd tetrahedron鈥搕ungsten oxide nanosheet hybrids (Pd/W₁₈O₄₉) to improve the electrocatalytic activity and stability of Pd nanocrystals. The hybrid materials are synthesized by direct nucleation, growth, and anchoring of Pd tetrahedral nanocrystals on the in situ-synthesized W₁₈O₄₉ nanosheets. Compared to supportless Pd nanocrystals and W₁₈O₄₉, their hybrids exhibited not only surprisingly high activity but also superior stability to Pt for the ORR in alkaline solutions. X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and electrochemical analyses indicated that the enhanced electrocatalytic activity and durability are associated with the increased number and improved catalytic activity of active sites, which is induced by the strong interaction between the Pd tetrahedrons and W₁₈O₄₉ nanosheet supports. The present study provides a novel strategy for synthesizing hybrid catalysts with strong chemical attachment and electrical coupling between nanocatalysts and supports. The strategy is expected to open up exciting opportunities for developing a novel class of metal-support hybrid nanoelectrocatalysts with improved ORR activity and durability for both fuel cells and metal鈥揳ir batteries.