Enhanced Supercapacitor Performance through Morphology Engineering of CNC-Derived Chiral Nematic Activated Carbon
Lucas J Andrew1, Evan J Wong1, Zongzhe Li1
1Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.
Abstract:
Cellulose nanocrystals (CNCs) are of great interest for electrochemical energy storage systems owing to their large surface area, intriguing self-assembly, renewability, and surface functionality. The chiral nematic organization of CNCs enables free-standing, hierarchical electrode materials that upon carbonization can be used in supercapacitors. KOH-activated carbon aerogels from chiral nematic CNCs have been reported previously in the literature, but the optimization of their nanostructure for performance enhancement has not yet been explored. In this context, this article reports the use of a factorial experimental design process to systematically tune the morphology and porosity of these aerogels. Through careful manipulation of fabrication conditions assisted by Design of Experiments (DOE), aerogels with specific surface areas from 300 to 1600 m2 g-1 and micropore volumes of 30-70% are achieved, and the sample-to-sample variance in surface area has been decreased by an order of magnitude in comparison to previous work. The influence of these morphological features on specific capacitance and cycling stability of aerogel-based supercapacitor electrodes is explored, and the effect of chiral nematic organization is demonstrated. This systematic study─the first in the literature to investigate pore structure optimization in CNC-based aerogel electrodes─offers a blueprint for advances in electrode materials design for future energy storage applications.


