Energy Band Gap Investigation of Polystyrene Copper Oxide Nanocomposites Bombarded with Laser

Abstract

The presence of metal nanoparticles in polymer matrices modified their thermal, mechanical, electronic, optical and catalytic activity. Introduction of 2nd manipulation strategy, such as laser irradiation has enabled further tuning of the polymer-metal oxide nanocomposite (Polystyrene CuO Nanocomposite (PS CuO NCs)) properties. A low dose of laser irradiation to PS CuO NCs has enabled the investigation of the polymer molecular restructuring that depended on metal nanoparticle concentration and laser dosages. Copper oxide (CuO) nanoparticle was synthesized by the chemical reduction method and incorporated inside the polymer (Polystyrene) matrices. The 2nd manipulation strategy by using laser irradiation to these PS CuO NCs was later investigated through Ultraviolet-Visible (UV-Vis) and Fourier Transform Infrared (FTIR), Atomic Force Microscopy (AFM) and surface profiler in determining the energy band gaps of the bare PS and PS CuO NCs. The topography of the PS significantly changed after adding the copper oxide nanoparticles that filled the PS-interconnected pores with the spike. The decrease in energy band gaps of the PS CuO NCs when exposed to laser irradiation confirmed the restructuring of the PS molecules into carbonaceous materials which corresponded to laser dosages and metal nanoparticles concentration. The energy band gaps of the PS MNCs can be tuned from 4.29 eV (non-radiated) to 1.4-1.95 eV proves that the energy band gaps of PS MNCs can be modified using two manipulation factors, which are metal nanoparticles concentration and laser dosages. The energy gaps of the PS MNCs are able to be tuned from Insulator-Semiconductor-Conductor and the carbonaceous materials ranging from graphite, graphene to diamond-like carbon.