Breaking Force and Conductance of Gold Nanojunctions: Effect of Humidity

J Phys Chem Lett. 2014 Oct 16;5(20):3560-4. doi: 10.1021/jz5019459. Epub 2014 Oct 7.

Abstract

Forces acting on elongated gold nanojunctions and their electric conductance were simultaneously measured by current-sensing force spectroscopy in an atmosphere with controlled humidity. The breaking force of "thick" nanojunctions with conductance >20G0 is not affected by the environmental humidity. The presence of ambient water stabilizes "thin" nanojunctions with conductance <15G0, whose breaking force of 10-15 nN was higher than that in a dry atmosphere due to the capillary forces. The observed effect of humidity would not be possible to distinguish by techniques measuring only forces or only conductance in nanojunctions.

Keywords: adhesion; break junction; breaking force; current sensing atomic force microscopy; humidity; metal nanocontacts; nanoscale conductance.