Tailoring the Optical Properties of Polyvinyl Alcohol/Carboxymethyl Cellulose/Polyvinyl Pyrrolidone Blend Films Using Laser Irradiation for Their Application in Optoelectronic Devices

Abstract

In our research described in this article we used a solution casting technique to prepare a blend film containing polyvinyl alcohol (PVA), carboxymethyl cellulose (CMC) and polyvinyl pyrrolidone (PVP). Samples from the prepared PVA/CMC/PVP film were irradiated with infrared energy fluences ranging from 5 to 55 Joule/cm2 using an infrared pulsed laser. We used UV-vis spectroscopy and the International Commission on Illumination (CIE) color changes technique to investigate the resulting effects of the laser irradiation on the optical bandgap energy and color properties of the prepared films. As the laser fluence increased up to 55 Joule/cm2, the maximum fluence used, both the direct and indirect bandgaps decreased. We attribute this to the dominance of chain crosslinks that destroyed the ordered structure and thus increased the amorphous regions. The effect of laser irradiation on the absorbance, refractive index, real and imaginary dielectric parameters and optical conductivity of the blend samples were studied. Furthermore, the optical color changes between the pristine and the irradiated films were evaluated. The pristine blend film was uncolored. It showed significant color changes when irradiated with the laser at increasing fluences up to 55 Joule/cm2. The improvement in the optical properties of PVA/CMC/PVP blend film suggested its usage as a promising candidate for future optoelectronics manufacturing.