Electrochemistry of partially unzipped carbon nanotubes

•CNTs were longitudinally cut to give PUCNTs.•The outer graphene-like structure of PUCNTs benefits for electrochemical activity.•The inner tube-like structure of PUCNTs could sustain high electrical conductivity.

Despite several pioneering work, the fundamental study of partially unzipped carbon nanotubes (PUCNTs) as an electrode material has hardly been done. In this work, we synthesized PUCNTs by solution-based longitudinal unzipping of carbon nanotubes (CNTs) and rigorously studied their electrochemical characteristics by using three representative redox probes. Electrochemical measurements reveal the superior electrochemical response of PUCNTs in comparison with CNTs, which can be attributed to the unique CNT–graphene complex structure of PUCNTs. Besides, for the three redox probes involved, the electron transfer kinetics of PUCNTs behave variously, indicating that the extent to which structural features affect electron transfer rates depends on the analytes. Our work suggests the great potential of PUCNTs as a sort of new electrode material for future electrochemical applications.