A general and scalable approach to produce nanoporous alloy nanowires with rugged ligaments for enhanced electrocatalysis
A general and scalable approach to produce nanoporous alloy nanowires with rugged ligaments for enhanced electrocatalysis
复制标题
一种通用且可扩展的方法来生产具有坚固韧带的纳米多孔合金纳米线，以增强电催化作用
DOI：
10.1039/c8ta03544j
复制
发表时间：
2018-07-14
影响因子：
11.9
通讯作者：
Liu, X. J.
中科院分区：
文献类型：
--
作者：
Qiu, H. -J.;Gao, J. J.;Liu, X. J.
Nanoporous metal nanowires with large surface areas, and a high density of defect sites play an important role in catalysis. Here, a general and scalable one-step dealloying strategy is developed to prepare nanoporous alloy nanowires with controllable compositions by manipulating the grain size, structure and composition of bulk Cu-based precursor alloys. We prepared PtCuAu nanoporous nanowires with a diameter of 200–500 nm and tunable composition by dealloying a diluted Pt1Au0.5Cu98.5 single-phase alloy with nanoscale column-like-structured grains. Material characterization suggests that the formation of separated nanowires is due to the large-scale shrinkage of the column-structured grains during dealloying of Cu, which also generates ultrafine nanopores and rugged alloy ligaments with a high density of defect sites in the nanowires. When used as a cathodic catalyst for the oxygen reduction reaction (ORR), the PtCuAu nanoporous nanowires exhibit a composition-dependent catalytic performance. The 8.0 M HNO3 dealloyed sample exhibits a specific activity of 4.12 mA cm−2 at 0.9 V, which is more than 14 times that of commercial Pt/C. With the advantages of being easy to scale up, highly reproducible and controllable, the fabrication strategy holds great promise to prepare nanocatalysts for fuel cells.
