Nanocellulose-based materials functionalized with reduced graphene oxide and titanium dioxide for potential applications in electronic devices

Abstract The growing demand for sustainable functional materials has driven the development of biocomposites with advanced electrical properties from renewable sources. This study presents electroconductive films made from nanocellulose obtained from agave bagasse, a lignocellulosic agroindustrial residue. Two types of nanocellulose were prepared: nanocrystals (CNCs) and nanofibrils (CNFs), which were combined with titanium oxide and reduced graphene oxide (RGO) to improve their conductive properties. Characterization was carried out using Raman spectroscopy, FTIR, X-ray diffraction, and atomic force microscopy. CNCs showed a higher crystallinity index (84%) compared with CNFs (67%), while FTIR spectra of CNCs displayed functional groups introduced during sulfuric acid hydrolysis. Raman spectroscopy of RGO showed an ID/IG ratio of 0.93, confirming its reduced state and partial recovery of the graphitic structure. AFM images revealed that CNCs were short rod-like particles with diameters of about 16 ± 6 nm and lengths near 65 ± 19 nm, whereas CNFs appeared as longer and thinner fibers with average lengths of 500 ± 45 nm. Electrical evaluation revealed that the CNCs films achieved conductivities of up to 23.2 S/m, in contrast to the CNF/TiO 2 -RGO films, which presented significantly lower values (on the order of 10 −4 S/m). This difference is attributed to the higher degree of crystallinity, smaller particle size, and better structural order of the CNCs, which favor charge transport. The results demonstrate the potential of nanocellulose for biodegradable conductive materials, with possible applications in flexible electronics, sensors, and energy storage, while supporting the valorization of agricultural waste. Graphical abstract