Piezoelectric sensitivity of a layered film of chitosan and cellulose nanocrystals

Abstract

Free-standing biodegradable films were fabricated by mixing cellulose nanocrystals and nanofibers with a water-based chitosan solution. The piezoelectric sensitivity of the films was measured to find out their suitability in sensing and actuation applications. Also their structure was evaluated with scanning electron microscopy. Our initial results show that a simple solvent casting method can be used to prepare films with varying piezoelectric properties. The composite films of chitosan and cellulose nanocrystals were noticed to have a phase-separated layered structure, resulting in an interesting side-dependent piezoelectric response. Moreover, the sensitivity values of plain chitosan were close to those of a non degradable commercial sensor material polyvinylidene fluoride. The fabrication process has to be studied further to control and optimize the structure and piezoelectric properties of the films.