Effect of Wet and Dry Environments in CNC/MWCNTs/Ag2O Electrically Conductive Films: Material Characterization and Molecular Dynamics Simulation

Electrically conducting biobased materials present a bright future for high-technological applications including sensors, soft electronics, and active packaging. Accordingly, here, we develop and characterize ternary nanohybrid films combining cellulose nanocrystals (CNC), multiwalled carbon nanotubes (MWCNTs) and silver oxide (Ag2O) nanoparticles. An evaporation-induced self-assembly process is applied to obtain homogeneously dispersed free-standing nanocomposite films as proven by electron microscopy. Thermogravimetric analyses show that MWCNTs delay the cleavage of glycosidic linkages of cellulose, while Ag2O catalyzed thermodegradation events rendering reduced thermal stabilities. The electrical and dielectrical properties are analyzed under completely dry and 53% humidity atmospheres, and the results are observed also in light of the electric modulus. Water increases the conductivity of binary and ternary systems and shifts the electric modulus relaxation peak. Finally, full atom molecular dynamics (MD) simulations are performed to describe the phenomena on interfaces between nanoscale systems, underlying mechanisms for the obtained electrical AC and DC results. Computational results reveal changes in the CNC/MWCNT/Ag2O interactions depending on the water content. The combination of experimental and simulation data shown sheds light on the electric conducting mechanism of nanocellulose-based materials with multifunctional properties.

Automated summary

Electrically conducting biobased materials have great potential for high-technological applications such as sensors, soft electronics, and active packaging. In this study, ternary nanohybrid films composed of cellulose nanocrystals (CNC), multiwalled carbon nanotubes (MWCNTs), and silver oxide (Ag2O) nanoparticles are developed and characterized. The electrical and thermal properties of the films are analyzed, and the effects of water content on the interactions between nanoscale systems are investigated using computational simulations.