Structure analysis and nonlinear/linear optical properties of PVAOH/Si composites for low-cost optical technologies and limiting absorption

Abstract

Optical limiting is considered one of the significant unusual applications that attract the attention of many scientists. In this study, we synthesized a novel flexible composite of silicon (Si)-doped polyvinyl alcohol (PVAOH) for this purpose. The preparation of the present polymeric film with different Si weight percentage was prepared by casting technique. The X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive analysis spectroscopy of X-rays (EDX), and Fourier-transform infrared spectroscopy (FTIR) have been carried out. Also, UV–Vis–NIR spectroscopy has been used to test the optical interpretation of the as-prepared films. The analysis of the structure reveals substantial integration between the two current phases. The SEM images created to the samples indicate an increase in surface roughness with the Si- substantive. The addition of Si to the virgin PVAOH has an impact on the optical properties such as the indirect optical energy gap (Eg), the arrangement of the localized state (Eu), absorption coefficient, and optical conductivity response. Depending on different models like Moss, Herve–Vandamme, Ravindra, and Singh-Kumar, the relation between the refractive index and the energy gap has been explored. Besides, the linear together with nonlinear optical assets of PVAOH/xSi polymer composites were investigated. The limiting aspects of the sample absorption were explored by employing different wavelengths (635 and 532 nm) coming from the He–Ne and green diode laser sources. The PVAOH/0.1Si film revealed significant optical advantages along with high optical laser limitation, recommending this could be a petitioner for different nonlinear technological devices and laser shields.