Easy decoration of carbon nanotubes with well dispersed gold nanoparticles and the use of the material as an electrocatalyst

A simple method has been developed to directly attach gold nanoparticles (Au-NPs) on carbon nanotubes (CNTs) with high dispersivity by using a small amount of ethanol to reduce the interfacial tension between CNTs and aqueous solution and impart solubility for CNTs in the solution containing Au-NPs. Both SEM and TEM characterization showed that Au-NPs distributed uniformly on the walls of CNTs. UV–vis spectra of the solution before and after attachment revealed that Au-NPs in the original solution were completely loaded on the CNTs without loss of Au source. The content of Au-NPs on CNTs could be controlled readily by adjusting the weight ratio between Au particles and CNTs. The electrochemical catalytic properties of the so-produced composites were characterized, and the samples showed a catalytic activity for the oxygen reduction reaction that is higher than those reported in the literature.