Unzipping Multiwalled Carbon Nanotubes under Vortex Fluidic Continuous Flow

Conventional batch processing in terms of unzipping multiwalled carbon nanotubes (MWCNTs) suffers from discontinuity, safety and environmental issues, reproducibility, and limited scalability. We have established a continuous-flow, scalable, and safe process for unzipping MWCNTs, achieving a yield of 75% under flow conditions, without the need for any auxiliary reagents. This involves using a mild oxidant, aqueous hydrogen peroxide, and harnessing the mechanical energy in a vortex fluidic device (VFD) while operating at ambient temperature. The physical properties of the fabricated unzipping MWCNTs were investigated by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, powder X-ray diffraction, and Raman spectroscopy. This scalable, continuous-flow VFD-enabled fabrication method for unzipping MWCNTs unveils the power of a fluidic vortex confined in a thin film of liquid for nanocarbon structural re-formation and functionalization.