Self-healing of fractured one-dimensional brittle nanostructures

J. Wang^1,2,3,4, C. Lu^1a, Q. Wang^3b, P. Xiao⁴, F. J. Ke^2,4, Y. L. Bai⁴, Y. G. Shen⁵, Y. B. Wang⁶, X. Z. Liao⁶ and H. J. Gao⁷

¹ Department of Mechanical Engineering, Curtin University - Perth, WA 6845, Australia
² School of Physics and Nuclear Energy Engineering, Beihang University - Beijing 100191, China
³ School of Aeronautics Science and Engineering, Beihang University - Beijing 100191, China
⁴ State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences Beijing 100190, China
⁵ Department of Mechanical and Biomedical Engineering, City University of Hong Kong Kowloon, Hong Kong, China
⁶ School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney Sydney, NSW 2006, Australia
⁷ School of Engineering, Brown University - Providence, RI 02912, USA

^a C.Lu@curtin.edu.au
^b bhwangqi@sina.com

Received: 9 February 2012
Accepted: 14 March 2012

Abstract

Recent experiments have shown that fractured GaAs nanowires can heal spontaneously inside a transmission electron microscope. Here we perform molecular-dynamics simulations to investigate the atomic mechanism of this self-healing process. As the distance between two fracture surfaces becomes less than 1.0 nm, a strong surface attraction is generated by the electrostatic interaction, which results in Ga–As re-bonding at the fracture site and restoration of the nanowire. The results suggest that self-healing might be prevalent in ultrathin one-dimensional nanostructures under near vacuum conditions.