Pristine graphene modulation of vertical colloidal deposition for gold nanoparticle wires

Abstract

Vertical colloidal deposition has emerged as an eco-friendly method for assembling nanoparticles into functional bulk structures. This technique is based on the coffee-ring effect, a natural dewetting phenomenon by which suspended particles in solution aggregate at a solid-liquid-gas interface. Significant research efforts have been devoted to developing and characterizing methods of modulating the coffee-ring effect, which offer additional degrees of control for vertical colloidal deposition. Functional nanoparticle conglomerates are often composed of gold nanoparticles, and studies of the coffee-ring effect have featured graphene materials. Moreover, some newly proposed technologies integrate graphene and gold nanoparticles. Here, we examine the effects of pristine graphene nanoflakes on vertical colloidal deposition for gold nanowires. Absorption measurements, for probing electrostatic changes, of colloidal mixtures of gold and graphene nanoparticles are presented, and the structural and electronic properties of the resulting wires are characterized. Our results suggest that pristine graphene modulates colloidal deposition of gold nanoparticles through jamming.