1. Introduction
Since carbon nanotubes （CNTs） were discovered by Iijima in
1991 [1], they have obtained much attention in nanoscale science
because of their distinctive optical, electronic and mechanical
properties [2,3]. CNTs, including single-walled carbon nanotubes
（SWNT） and multi-walled carbon nanotubes （MWNT）, possess subtle
electronic properties and efficient catalytic activity, revealing
that they are ideal electrode materials and have promising applications
in electrochemistry [4]. However, the insolubility of CNTs represents
a barrier to fabricate CNTs film-modified electrode [5,6]. In
order to overcome this difficulty and develop novel CNTs film electrode,
various methods such as dispersing CNTs into N,N-dimethyl
formamide （DMF） [5], Nafion solution [6,7], acetone [8] and dihexadecyl
hydrogen phosphate （DHP） [9–12], have been reported.