Anomalous low strain induced by surface charge in nanoporous gold with low relative density

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	Anomalous low strain induced by surface charge in nanoporous gold with low relative density
	Liu, Feng; Ye, Xing-Long; Jin, Hai-Jun; Jin, HJ (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Liaoning, Peoples R China.
	2017-08-07
发表期刊	PHYSICAL CHEMISTRY CHEMICAL PHYSICS
ISSN	1463-9076
卷号	19 期号:29 页码:19217-19224
摘要	The surface stress induced axial strain in a fiber-like solid is larger than its radical strain, and is also greater than the radical strain in similar-sized spherical solids. It is thus envisaged that the surfaceinduced macroscopic dimension change (i.e., actuation strain) in nanoporous gold (NPG) increases with decreasing relative density, or alternatively, with an increasing ratio between volumes of fiber-like ligaments and sphere-like nodes. In this study, electrochemical actuations of NPG with similar structure sizes, same (oxide-covered) surface state but different relative densities were characterized in situ in response to surface charging/ discharging. We found that the actuation strain amplitude did not increase, but decreased dramatically with decreasing relative density of NPG, in contrast to the above prediction. The actuation strain decreased abruptly when the relative density of NPG was decreased to below 0.25, when the Au content in the AuAg precursor was below 20 at%. Further studies indicate that this anomalous behavior cannot be explained by potential-or size-dependences of the elasticity, the structure difference arising from different dealloying rates, or additional strain induced by the external load during dilatometry experiments. In NPG with low relative density, mutual movements of nanoligaments may occur in the pore space and disconnected regions, which may compensate the local strain in ligaments and account for the anomalous low actuation strain in macroscopic NPG samples.; The surface stress induced axial strain in a fiber-like solid is larger than its radical strain, and is also greater than the radical strain in similar-sized spherical solids. It is thus envisaged that the surfaceinduced macroscopic dimension change (i.e., actuation strain) in nanoporous gold (NPG) increases with decreasing relative density, or alternatively, with an increasing ratio between volumes of fiber-like ligaments and sphere-like nodes. In this study, electrochemical actuations of NPG with similar structure sizes, same (oxide-covered) surface state but different relative densities were characterized in situ in response to surface charging/ discharging. We found that the actuation strain amplitude did not increase, but decreased dramatically with decreasing relative density of NPG, in contrast to the above prediction. The actuation strain decreased abruptly when the relative density of NPG was decreased to below 0.25, when the Au content in the AuAg precursor was below 20 at%. Further studies indicate that this anomalous behavior cannot be explained by potential-or size-dependences of the elasticity, the structure difference arising from different dealloying rates, or additional strain induced by the external load during dilatometry experiments. In NPG with low relative density, mutual movements of nanoligaments may occur in the pore space and disconnected regions, which may compensate the local strain in ligaments and account for the anomalous low actuation strain in macroscopic NPG samples.
部门归属	[liu, feng ; ye, xing-long ; jin, hai-jun] chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, liaoning, peoples r china ; [liu, feng] univ chinese acad sci, beijing 100049, peoples r china
学科领域	Chemistry, Physical ; Physics, Atomic, Molecular & Chemical
资助者	National Natural Science Foundation of China [51571206]; Natural Science Foundation of Liaoning Province [2014029103]; External Cooperation Program of Chinese Academy of Sciences
收录类别	SCI
语种	英语
WOS记录号	WOS:000406334300041
引用统计	被引频次：13[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/78023
专题	中国科学院金属研究所
通讯作者	Jin, HJ (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Liaoning, Peoples R China.
推荐引用方式 GB/T 7714	Liu, Feng,Ye, Xing-Long,Jin, Hai-Jun,et al. Anomalous low strain induced by surface charge in nanoporous gold with low relative density[J]. PHYSICAL CHEMISTRY CHEMICAL PHYSICS,2017,19(29):19217-19224.
APA	Liu, Feng,Ye, Xing-Long,Jin, Hai-Jun,&Jin, HJ .(2017).Anomalous low strain induced by surface charge in nanoporous gold with low relative density.PHYSICAL CHEMISTRY CHEMICAL PHYSICS,19(29),19217-19224.
MLA	Liu, Feng,et al."Anomalous low strain induced by surface charge in nanoporous gold with low relative density".PHYSICAL CHEMISTRY CHEMICAL PHYSICS 19.29(2017):19217-19224.