Preparation of homogeneously dispersed and highly concentrated double-walled carbon nanotubes as catalyst support

In this study, double-walled carbon nanotubes （DWCNTs） in ethylene glycol （EG） and N,N-dimethyl- formamide （DMF） media were investigated by a simple ultrasonication method. Homogeneously dispersed and highly concentrated DWCNTs are in EG （95 vol%） and DMF （5 vol%） media without the addition of surfactant. Surface structure and crystallinity of DWCNTs undergo minimal change. The highly concentrated dispersion state of DWCNTs helps in Pt loading. Pt particles prepared in the homogenous dispersion system have small sizes and are uniformly distributed. The prepared Pt catalysts display a similar electrochemical activity to catalysts pre- pared in EG system with low concentration. The results demonstrate that homogenously dispersed and highly concentrated DWCNTs can realize mass production of Pt/ DWCNT catalysts with high electrochemical activity and low cost.