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In the present study, europium (III) oxide (Eu2 O3 )-doped polystyrene (PS) polymer films were synthesized using a solution-casting technique for different filler levels. These films were irradiated with 5, 25 and 50 kGy γ doses and characterized using various techniques, viz. X-ray diffraction (XRD), and UV-visible and photoluminescence (PL) spectroscopies as a function of composition level and radiation dose. The UV-visible spectra indicated a decrease in the optical direct band gap of composite films with increasing concentrations of dopant and radiation dose. The band gaps of composites obtained using Tauc's equation were found to be 4.38, 4.37, 4.36 and 4.34 eV for 0, 1, 3 and 5% Eu2 O3 -doped PS respectively, while the band gaps of 5% Eu2 O3 -doped PS polymer films irradiated with 5, 25 and 50 kGy were found to be 4.30, 4.26 and 4.21 eV, respectively. Photoluminescence (PL) emission spectra showed the characteristic peaks of Eu3+ at 595 nm, 612 nm and 617 nm with an excitation wavelength of 247 nm. The intensity of characteristic peaks of Eu3+ was observed to increase with increasing filler concentration, while it was found to decrease with increasing radiation dose. The polymer under study may be useful in accidental dosimetry. As photoluminescence studies are carried out after a gap of 200 h from irradiation and PL emission of γ-irradiated polymer yielded 10 times emission when compared with non-irradiated polymer.

Effect of swift heavy ion irradiation on electrical and optical properties of chitosan-based solid polymer electrolyte system, prepared by the solution casting technique, was investigated. The solid polymer electrolyte films were irradiated with C +5 and Ni +7 ions of energy 60 and 100 MeV, respectively, at different fluences. X-ray diffraction (XRD) analysis revealed the transformation of chitosan structure to the amorphous phase due to the addition of salt. FTIR spectra showed diverse vibrational modes and scissioning of bonds due to ion beam irradiations. Ions produce volatile low-molecular-weight species and results in the evolution of gas during irradiation processes. The polymer electrolyte became carbon rich with more conjugated bonds and diminished the band gap, as found by the UV–Vis analysis. The variable parameters obtained by the Bergman fitting specify that the relaxation process in the polymeric matrix is non-Debye, and the conductivity of electrolyte enhanced as a function of beam parameters.

Self-sustained films of biodegradable chitosan (CS) and chitosan-Ag nanocomposites (CSN) were prepared by chemical route followed by C+5 and Ni+7 ions irradiation with varying fluences. The crystallite size decreased from 11.1 to 2.7 nm for CS and 17.6 to 14.2 nm for CSN with increasing ions fluence as observed from the analysis of X-ray Diffraction (XRD) spectra. ATR-FTIR spectra revealed assorted vibrational modes and degradation of polymeric chains in both, CS and CSN matrices upon irradiation. The molecular interactions between main and side-chain functional groups impeded due to nanoparticles confining effects. MeV ions yield low-molecular-weight fragments with degassing of some volatile gaseous species during irradiation. An acute amendment in absorption spectra ascribed to change in surface color and differential absorbance at the wavelength of 370 nm showing blocking of UV radiation. The formation of conjugated linkages and carbonization of CS and CSN matrices lead to decrease in bandgap. Modifications in the physicochemical properties were found to be in persuasive association with changes in frequency-dependent dielectric responses. The shape parameter was moderately decreased and indicating non-Debye relaxation. The conductivity of CS and CSN matrices enhanced and follows the universal dielectric response. The amendment in surface morphology was also revealed upon irradiation.

Poly ethylene oxide (PEO) films were synthesized by solution cast method. These self-standing films were exposed with 60 MeV C +5 ion and 100 MeV Ni +7 ion at different fluences. SHI induced effect was investigated by employing various techniques. The crystalline size decreased upon irradiation as observed from XRD analysis. FTIR analysis reveals the decrement in the peak intensity upon irradiation. Tauc’s method was used to determine the optical band gap ( E g ), which shows decreasing trends with increase of fluence. The dielectric properties were investigated in the frequency range 10 Hz to 10 MHz for unirradiated and irradiated films. The dielectric constant remains same for the broad-spectrum of frequency and increases at lower frequency. The dielectric loss also moderately influence as a function of frequency due to irradiation. DSC analysis validated the results of XRD. Scanning electron microscopy (SEM) reveals that there is significant change in the surface morphology due to irradiation.