Xu Hui, Song Pingping, Yan Bo, Wang Jin, Wang Caiqin, Shiraishi Yukihide, Yang Ping, Du Yukou
College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China.
Tokyo University of Science Yamaguchi, Sanyo-Onoda-shi, Yamaguchi, 756-0884, Japan.
ChemSusChem. 2018 Mar 22;11(6):1056-1062. doi: 10.1002/cssc.201702409. Epub 2018 Feb 8.
Precise control of structures offers a great opportunity to efficiently tune the catalytic performance of nanomaterials, enhacing both their activity and durability. Herein, we achieve a new class of Pt islands on 3 D nut-like PtAg nanocrystals by exploiting the lower electronegativity of Ag in conjunction with the galvanic replacement of catalytically active Pt to Ag. Such nanostructures coated with Pt nanoparticles, exhibiting exposed facets, and active surface composition enhance formic acid oxidation electrocatalysis with optimized PtAg nut-like catalysts and achieved a factor of 4.0 and 2.4 in mass and specific activities (1728.3 mA mg and 3.31 mA cm ) relative to those of the commercial Pt/C (431.2 mA mg and 1.41 mA cm ), respectively. Moreover, such 3 D PtAg nut-like catalysts also display great enhancement in durability with less decay for at last 500 cycles, showing a great potential to serve as promising catalysts for fuel cells and other applications. Our work provides a fundamental insight on the effect of the morphology toward liquid fuel electrooxidation, which may pave a new way for the fabrication of highly efficient electrocatalysts for fuel cells.
对结构的精确控制为有效调节纳米材料的催化性能提供了绝佳机会，可同时提高其活性和耐久性。在此，我们通过利用银较低的电负性以及将催化活性的铂电置换为银，在三维螺母状铂银纳米晶体上实现了一类新型的铂岛。这种涂覆有铂纳米颗粒的纳米结构，具有暴露的晶面和活性表面组成，通过优化的铂银螺母状催化剂增强了甲酸氧化电催化性能，相对于商业铂碳催化剂（431.2 mA mg和1.41 mA cm），其质量活性和比活性分别达到4.0倍和2倍（1728.3 mA mg和3.31 mA cm）。此外，这种三维铂银螺母状催化剂在耐久性方面也有显著增强，在至少500次循环中衰减较小，显示出作为燃料电池和其他应用中很有前景的催化剂的巨大潜力。我们的工作为形态对液体燃料电氧化的影响提供了基本见解，这可能为制造用于燃料电池的高效电催化剂开辟一条新途径。
