Role of Metals Content in Spinach in Enhancing the Conductivity and Optical Band Gap of Chitosan Films

Abstract

Blend of chitosan and spinach extract has been successfully prepared using acetic acid as a solvent medium to produce chitosan-spinach films. The conductivity measurements showed that chitosan-spinach films for all ratios of 95 : 5, 90 : 10, 85 : 15, and 80 : 20 had better conductivity than the chitosan film. The optical band gap reduced with the addition of the spinach extract into chitosan. Chitosan-spinach film with the ratio of 85 : 15 gave the best electrical properties in this work with the conductivity of 3.41 × 10−6 S/m and optical band gap of 2.839 eV. SEM-EDX spectra showed the existence of potassium, phosphorus, sulphur, iron, and oxygen in chitosan-spinach films. AFM image showed that the surface morphology of the films became rougher as the spinach incorporated into chitosan. The minerals which exist in spinach extract play a role in enhancing electrical properties of chitosan film.