Investigating the differences in the optical properties and laser photoluminescence for chitosan films extracted from two different origins

Abstract

This work carefully examines the variations in chitosan films derived from shrimp and crab shells in terms of their optical characteristics and laser-induced photoluminescence. Chitosan was dissolved in acetic acid and then cast into films to create chitosan films. The functional properties of chitosan generated from crab and prawns were shown to differ in specific spectrum regions due to differences in hydrogen bonding, degree of deacetylation, and structural conformations, as indicated by the FTIR study. Using TD-DFT and TD-DFT/CASTEP simulations, computational studies were carried out to predict the chitosan samples' molecular structures and frequency characteristics. Measurements and analyses were done on the optical characteristics, such as absorbance, refractive index, dielectric constants, and optical conductivity. Chitosan from shrimp shells (chitosan 2) and crab shells (chitosan 1) differed significantly in terms of UV absorbance, refractive index, dielectric constant, and optical conductivity, according to the study. Chitosan 2 showed increased dielectric constant, refractive index, and UV absorbance, indicating higher optical conductivity and a larger capacity for electrical energy storage, making it a better fit for optoelectronic applications. Chitosan's optical and photoluminescence characteristics are greatly influenced by its place of origin. These results emphasize how crucial it is to choose the right source material for a given optical application, especially in domains, where precise control over UV absorption and refractive index is necessary.