Assembling tin dioxide quantum dots to graphene nanosheets by a facile ultrasonic route

Nanocomposites have significant potential in the development of advanced materials for numerous applications. Tin dioxide (SnO₂) is a functional material with wide-ranging prospects because of its high electronic mobility and wide band gap. Graphene as the basic plane of graphite is a single atomic layer two-dimensional sp² hybridized carbon material. Both have excellent physical and chemical properties. Here, SnO₂ quantum dots/graphene composites have been successfully fabricated by a facile ultrasonic method. The experimental investigations indicated that the graphene was exfoliated and decorated with SnO₂ quantum dots, which was dispersed uniformly on both sides of the graphene. The size distribution of SnO₂ quantum dots was estimated to be ranging from 4 to 6 nm and their average size was calculated to be about 4.8 ± 0.2 nm. This facile ultrasonic route demonstrated that the loading of SnO₂ quantum dots was an effective way to prevent graphene nanosheets from being restacked during the reduction. During the calcination process, the graphene nanosheets distributed between SnO₂ nanoparticles have also prevented the agglomeration of SnO₂ nanoparticles, which were beneficial to the formation of SnO₂ quantum dots. © 2013 American Chemical Society.