Carbon Nanotube Highly Dispersed by Eco-Friendly Alkyl Chain-Bridged Lignin-Based Polymer and Its Properties

In this study, carbon nanotube (CNT) suspensions were highly dispersed using an alkyl chain-bridged lignin polymer. UV-vis and Fourier transform infrared spectroscopy (FTIR) were applied to characterize the structure of functionalized CNT products. The result demonstrates that functionalized CNTs have been successfully prepared. The photo, particle size distribution analysis, and SEM imaging showed that the dispersion efficiency of CNT suspension was significantly improved. Cyclic voltammetry (CV) was used to test the oxidation-reduction properties of CNT products. The results showed that all CNTs exhibit an obvious redox peak, and the oxidation potential decreases slightly with the increase of lignin polymer dosage. The results of conductivity and impedance also showed that the 1% ASL can effectively reduce electrochemical impedance and significantly enhance the electrochemical performance of CNTs. TG was used to investigate the thermal stability of the CNT products. The results showed that the stability of functionalized CNTs is relatively excellent, with a residual mass of up to 97% at 250 °C. Moreover, the degree of defect and disorder was reduced after doping with lignin-based polymer. It has been successful in addressing the limitations of CNTs and facilitating their application. Above all, the results show that CNT suspension can be highly dispersed by eco-friendly lignin-based polymer, which will facilitate its application as an electrode material and widen the potential applications of lignin.