Optical properties of pure and doped PMMA-CO-P4VPNO polymer films

Abstract

Optical properties like direct and indirect optical energy gap, optical absorption edge were investigated in pure and doped polymethyl-methacrylate-co-poly4vinyl pyridine N-oxide (PMMA-CO-P4VPNO) films from their optical absorption spectra in 300–550 nm wavelength region. The direct optical energy gap for pure PMMA-CO-P4VPNO lay at 3.76 eV while it ranged from 3.74 to 3.66 eV for differently doped samples. Similar behaviour was seen for indirect optical energy gap and absorption edge. It was found that the energy gaps and band edge values shifted to lower energies on doping with KBrO 3, KClO 3 and KIO 3 salts up to a dopant concentration of 10% wt.