Recent progress in carbon nanotube (CNT) separation has allowed colloidal CNTs to be prepared with controlled length, diameter, and surface coating composition. This opens up the possibility of using purified CNTs as an ideal rod-like particle system to explore general colloidal behavior in high concentrations of polymers and salts. Interesting phenomena include CNT length dependent phase separation, with morphology of the CNT-rich phases ranging from nematic liquid-crystals to fractal aggregates; Hoffmeister effect in salt-induced CNT precipitation, and interfacial trapping of CNTs at polymer/polymer interfaces. This project aims at quantifying these colloidal behaviors in order to achieve fundamental understanding of the underlying molecular forces. Insight gained can be used for CNT sorting and orientation-controlled assembly of CNTs for electronic and photonic applications.

References

Khripin, et al: ACS Nano 5: 8258, 2011

Khripin, et al: JACS 135: 6822, 2013