Gamma irradiation effect on the structural and optical properties of manganese (III) phthalocyanine chloride films: Experimental and theoretical approach for optoelectronic applications

Irradiation using ionizing radiation such as gamma-ray alters the material characteristics of organic semiconductors, especially the optical and electronic properties. The potential changes of manganese phthalocyanine chloride (MnPcCl) films have been investigated after several gamma irradiation doses (50, 150, and 250 kGy). The possible chemical structure and electronic characteristics of MnPcCl dye were analyzed using the density functional theory-based quantum calculations. The X-ray diffraction of various gamma-ray doses confirmed the amorphous nature of MnPcCl. Based on UV-Vis-NIR spectrophotometric measurements, Tauc's method has been used to deduce the optical bandgap energy of MnPcCl films before and after gamma-irradiation. A slight non-linear reduction was observed in the optical bandgap energy, refractive index, and dielectric constant with rising gamma-irradiation doses. The reduction in these optical parameters was due to the increase in the defects and the disorder degree created by gamma-irradiation. The low effect on the optical parameters of MnPcCl films confirms its optical stability within this high range of gamma-irradiation doses. Such investigation highlights the scope for the stability of this organic dye after exposure to gamma-irradiation doses for use in optoelectronic/photonic technological devices.