Correlation between photoluminescence and optical properties of Makrofol® De 1-1 exposed to high flux of UVC

Abstract

The correlation between the induced modifications in the photoluminescence spectra and the optical energy band gaps upon exposure to short ultraviolet C (UVC) of 254 nm in the polymers-based solid state nuclear track detector Makrofol® De 1-1 were investigated. Samples of Makrofol® De 1-1 were exposed to UVC radiation of 254 nm for different durations in air, thereafter the UV–visible and photoluminescence spectra were measured. It was found that Makrofol®-De 1-1 shows substantial's modifications in its optical and fluorescence characteristics upon exposure to UVC with a wavelength of 254 nm. UV–visible spectra of UVC irradiated Makrofol® De 1-1 shows continues red shift. Furthermore, a shoulder was observed in the wavelength range from 300 to 330 nm. Both of the red shift and the absorbance at the shoulder increase with the increase in the exposure time which seems to be saturated at prolonged exposure times more than 180 min. Photoluminescence spectra of UVC irradiated Makrofol® De 1-1 show a reasonable modifications upon exposure to UVC with a wavelength of 254 nm. The width at the half height of the band peak and the red shift of the photoluminescence spectra increase with the increase in the exposure time till the exposure time of 180 min, thereafter no significant changes were observed. It is found that the red shift and width of the photoluminescence spectra are correlated with the optical energy band gaps upon UVC irradiation. The peak wavelength as well as the band width of the photoluminescence spectra increases with the decrease in the optical band gaps. This experiment can provide an integrated understanding of utilizing Makrofol® De 1-1 in low linear energy transfer radiation dosimetry by connecting the concepts of photoluminescence, optical band gaps, and carbon clusters.