Questioning liquid droplet stability on nanowire tips: from theory to experiment

Liquid droplets sitting on nanowire tips constitute the starting point of the vapor-liquid-solid

method of nanowire growth. Shape and volume of the droplet have been linked to a variety of

growth phenomena ranging from the modication of growth direction, nanowire orientation, crystal

phase, and even polarity. In this work we focus on numerical and theoretical analysis of the stability

of liquid droplets on nanowires tip, explaining the peculiarity of this condition with respect to the

wetting of planar surfaces. We highlight the role of the droplet pinning at the tip in engineering

the contact angle. Experimental results on the characteristics of In droplets of variable volume

sitting on the tips or side facets of InAs nanowires are also provided. This work contributes to the

fundamental understanding of the nature of droplets contact angle at the tip of nanowires and to

the improvement of the engineering of such nanostructures.