Efficient functionalization of multi-walled carbon nanotubes by nitrogen dioxide

•A novel idea of utilization NO2 as a “catalyst” to activate CNTs surface is proposed.•NO2 can efficiently open the end to give the largest specific surface area.•NO2 is more favorable to generate active qunione groups on CNTs surface.•The NO2-treated CNTs show a good catalytic performance of dehydrogenation of propane.

Nitrogen dioxide (NO2) as an oxidative agent can efficiently react with multi-walled carbon nanotubes (CNTs) and sequentially introduces large quantities of oxygen functional groups on the surface. The produced NO can be easily oxidized by O2 into NO2, achieving an almost close cycle of NOx. NO2 is more favorable to generate active qunione groups on CNTs surface and improve the specific surface area of CNTs. The NO2-treated CNTs show the superior catalytic performance for oxidative dehydrogenation of propane. This work provides an applicable and efficient method for the mass functionalization of CNTs and other carbon materials.

Graphical abstractNO2 can efficiently open the end and functionalize carbon nanotubes, improving the surface oxygen content and specific surface area. The treated CNTs displayed an outstanding catalytic performance for the oxidative dehydrogenation of propane.Figure optionsDownload full-size imageDownload as PowerPoint slide