Adsorption of graphene oxide with cellulose acetate: insights from DFT

Cellulose acetate(CA)/graphene oxide (GO) composites have been widely used in the drug development and biosensing due to its excellent biocompatibility and strength. It is important to study their adsorption mechanisms for the application of CA/GO in detail. Here, the interaction between GO and CA was described by DFT simulations, and CA/GO composite films were characterised using tensile testing and FTIR spectroscopy. DFT calculations indicated that there is no chemical bonding between CA and GO adsorption but hydrogen bonding from hydroxyl groups facilitates the adsorption process. FTIR of CA/GO results show that the characteristic peaks of hydroxyl groups in the composite film is shifted towards high frequencies compared to the pure CA film, which is a strong evidence of hydrogen bonding of hydroxyl groups during the adsorption process. The tensile test results indicate that hydrogen bonds contribute to the tensile strength and elastic modulus of the CA/GO composite film.