Structural characterization of the crystalline nanocellulose and nanocellulose-reinforced carbon buckypaper

Abstract

Recently, nanostructured cellulose materials have been taking great attention due to their excellent mechanical properties, nanostructure, and non-toxic nature. According to these amazing properties, nanocellulose has been suggested as an excellent reinforcement material to empower the carbon paper structure. In this study, experimental investigations were conducted to establish a comprehensive understanding of the fundamental characterizations of crystalline nanocellulose (CNC) material such as structure, morphology, crystallinity, dispersion characterizations, and thermal and electrical behavior. Moreover, the grinding effect on the CNC structure and morphology, the advantage of CNC reinforcement in carbon buckypaper (BP) properties and performances were investigated. As a result, structural and morphological studies indicated that the relative amount of crystal domain in the CNC is 66% which contains numerous sphere-shaped crystal nanoparticles composed of small crystallites with an approximate size of 42.33 nm. Therefore, the electrical conductivity of CNC aqueous dispersion was greatly improved with an increase of concentration but the opposite results found for the thermal conductivity. Compared to the non-ground and ground CNC structures, crystallinity and morphology were not able to maintain, dispersibility in aqueous media improved but not the dispersion stability. Moreover, the composite structure of obtained BP was revealed by TEM analysis, filtration, salt rejection and absorption ability of the fabricated buckypaper determined by UV-Vis spectral analysis and electrical conductivity measurement. The obtained nanocomposite CNT/CNC buckypaper exhibited 48% of improved salt rejection and excellent filtration and adsorption ability which can compete with traditional water filtration counterparts. Besides, the natural abundance and biodegradability of nanocellulose are the big-tickets to the low-cost and eco-friendly production of the nanocomposite paper substrate.