Primary and Secondary Dealloying of Au(Pt)-Ag: Structural and Compositional Evolutions, and Volume Shrinkage

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	Primary and Secondary Dealloying of Au(Pt)-Ag: Structural and Compositional Evolutions, and Volume Shrinkage
	X. L. Ye; N. Lu; X. J. Li; K. Du; J. Tan; H. J. Jin
	2014
发表期刊	Journal of the Electrochemical Society
ISSN	0013-4651
卷号	161 期号:12 页码:C517-C526
摘要	Systematic study of the dealloying of Au-Ag and Au(Pt)-Ag alloys shows that the dealloying occurs by two processes: a primary dealloying process that selectively dissolves Ag from the parent alloy and creates a nanoporous (np) structure, and a secondary dealloying process that occurs behind the corrosion front and further dissolves the residual Ag from the nano-ligaments. The secondary dealloying can occur during coarsening, and/or when a more anodic potential is applied. With suppressed np structure coarsening in Pt-containing samples, we found that the intrinsic np structure created by the primary dealloying contains small ligament diameter (3-7 nm) and high concentration of residual Ag (similar to 50 at.%), irrespective of the dealloying potentials. Dilatometry experiments show that the volume shrinkages are rather small during primary dealloying and are large during secondary dealloying. The primary dealloying can be explained by the percolation dissolution mechanism. Although the mechanism of the secondary dealloying (without coarsening) remains unclear, we point out that the kinetics of the secondary dealloying is decisive to some important characters of np metals, such as the crack formation and the final residual Ag concentrations. (c) 2014 The Electrochemical Society. All rights reserved.
部门归属	[ye, xing-long ; lu, ning ; li, xiao-ju ; du, kui ; tan, jun ; jin, hai-jun] chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china. ; ye, xl (reprint author), chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china. ; hjjin@imr.ac.cn
关键词	Stress-corrosion Cracking Au-pt Alloys Nanoporous Gold Noble-metal Porosity Evolution Fine-structures Low-temperature Binary-alloys Nanoparticles Dissolution
URL	查看原文
语种	英语
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/73476
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	X. L. Ye,N. Lu,X. J. Li,et al. Primary and Secondary Dealloying of Au(Pt)-Ag: Structural and Compositional Evolutions, and Volume Shrinkage[J]. Journal of the Electrochemical Society,2014,161(12):C517-C526.
APA	X. L. Ye,N. Lu,X. J. Li,K. Du,J. Tan,&H. J. Jin.(2014).Primary and Secondary Dealloying of Au(Pt)-Ag: Structural and Compositional Evolutions, and Volume Shrinkage.Journal of the Electrochemical Society,161(12),C517-C526.
MLA	X. L. Ye,et al."Primary and Secondary Dealloying of Au(Pt)-Ag: Structural and Compositional Evolutions, and Volume Shrinkage".Journal of the Electrochemical Society 161.12(2014):C517-C526.