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Cation and anion disordering affect the structural and electronic properties of the isometric A2B2O7 pyrochlore materials. Here, we report a study on the structural response of La2Zr2O7 at two different temperatures (300 K and ~88 K) as a function of ion fluence (1 × 1013, 5 × 1013, and 1 × 1014 ions/cm2). The effect of ion fluence and irradiation temperature on the structural properties have been investigated using the grazing angle x-ray diffraction, Raman spectroscopy, and high-resolution transmission electron microscopy. GIXRD results confirmed that the weakening/broadening of the diffraction peaks and lattice volume expansion increases monotonically as a function of ion fluence at both the temperatures and are more pronounced at ~88 K. The cation and anion disordering appear to be ion fluence and irradiation temperature-dependent. Raman spectroscopy shows that the atomic disordering is more pronounced with enhanced ion fluence and revealed the involvement of the X48f parameter in the enhancement of disordering in the system. The HRTEM analysis revealed that the deterioration in the atomic ordering (amorphization) is significantly more pronounced at ~88 K. The qualitative analysis of cation/anion disordering and structural deformation revealed that irradiation parameters play a crucial role in developing and altering the properties of the pyrochlore materials for the technological applications.

Structural and spectroscopy studies have been carried out on conducting polymer poly(3-octylthiophene) (P3OT) and its copper-doped ZnO (Cu-ZnO/P3OT) hybrid nanocomposites (HNCs) under swift heavy ion (SHI) irradiation at different electronic energy depositions. The photoluminescence (PL) spectra of irradiated films exhibit a significant decrease in the intensity of emissions at higher ion fluences which is ascribed to the trapping of a photo-induced electron-hole by irradiation-induced free radicals and extrinsic non-radiative trap centers leading to the quenching effects. The generation of such free radicals and non-radiative recombination centers occurred through a chemical transformation of polymers in terms of polymer chain disordering, chain scission, chain aggregation, and bond breaking by ion irradiation depending upon the electronic energy depositions and ion fluences. The structural, vibrational, morphological, and optical properties of the irradiated P3OT and Cu-ZnO/P3OT HNCs films have been studied. Interestingly, the glancing-angle x-ray diffraction patterns of irradiated films reveal that the polymer and HNC films retain their chemical structures after high electronic deposition at lower ion fluences which leads to insignificant degradation of polymer and HNCs. However, a relative change in the intensity of characteristic peaks of polymer and ZnO was observed at higher ion fluences and is attributed to the disordering of polymer chains by high electronic depositions. Fourier transform infrared spectroscopy (FTIR) measurements also show similar observation, attributed to a decrease in the intensity of a few methyl and octyl functional groups of P3OT and HNCs. Further, optical study has shown a significant modification in the process of inter-chain and interfacial charge transfer. Finally, from these concurrent effects, PL quenching and photo-induced charge carrier transfer processes are understood by developing a schematic charge transfer diagram.

In the present study, crystallization of amorphous-Si (a-Si) in Al/a-Si bilayer thin films under thermal annealing and ion irradiation has been investigated for future solar energy materials applications. In particular, the effect of thickness ratio (e.g. in Al : a-Si, the ratio of the Al and a-Si layer thickness) and temperature during irradiation on crystallization of the Si films has been explored for the first time. Two sets of samples with thickness ratio 1 : 1 (set-A: 50 nm Al/50 nm a-Si) and thickness ratio 1 : 3 (set-B: 50 nm Al/150 nm a-Si) have been prepared on thermally oxidized Si-substrates. In one experiment, thermal annealing of the as-prepared sample (of both the sets) has been done at different temperatures of 100 °C, 200 °C, 300 °C, 400 °C, and 500 °C. Significant crystallization was found to initiate at 200 °C with the help of thermal annealing, which increased further by increasing the temperature. In another experiment, ion irradiation on both sets of samples has been carried out at 100 °C and 200 °C using 100 MeV Ni7+ ions with fluences of 1 × 1012 ions per cm2, 5 × 1012 ions per cm2, 1 × 1013 ions per cm2, and 5 × 1013 ions per cm2. Significant crystallization of Si was observed at a remarkably low temperature of 100 °C under ion irradiation. The samples irradiated at 100 °C show better crystallization than the samples irradiated at 200 °C. The maximum crystallization of a-Si has been observed at a fluence of 1 × 1012 ions per cm2, which was found to decrease with increasing ion fluence at both temperatures (i.e. 100 °C & 200 °C). The crystallization of a-Si is found to be better for set-B samples as compared to set-A samples at all the fluences and irradiation temperatures. The present work is aimed at developing the understanding of the crystallization process, which may have significant advantages for designing crystalline layers at lower temperature using appropriate masks for irradiation at the desired location. The detailed mechanisms behind all the above observations are discussed in this paper.

Zirconolite, a potential candidate for the immobilization of actinides was investigated for the induced effects of α-particles simulated through ion beam irradiation. Nd-doped zirconolite pellets (Ca0.8Nd0.2ZrTi1.8Al0.2O7) synthesized through two step solid state sintering were irradiated with 30 keV He+ ions and analyzed for irradiation induced structural modulations through glancing angle X-ray diffraction technique. Diffraction patterns showed reduction in peak intensity and broadening of peaks with increasing fluence, indicating loss of crystallinity. Though zirconolite didn’t amorphize even upon irradiation at the maximum fluence used i.e. 1 × 1017 ions/cm2. Measured lattice strain enhanced with fluence, further suggesting distortion of the structure.

Synroc minerals have been studied since decades for immobilization of high-level radioactive wastes released from nuclear weapons and nuclear reactors. Among them, the zirconolite, due to its high radiation and aqueous resistance and high waste loading, is considered as a potential candidate for containment purposes. Though irradiation damage effects of swift heavy ions in the material remain a major concern of study, a single phase Nd-doped zirconolite samples prepared through conventional solid-state reaction were irradiated with 120 MeV Au+ ions to study radiation damage effects. Irradiation-induced effects were investigated using ex-situ XRD and micro-Raman spectroscopic techniques. Zirconolite has been observed to undergo amorphization which is confirmed through disappearance of characteristic x-ray diffraction peaks and appearance of broad diffuse scattering bands. Amorphization trend with fluence appeared linear at lower fluences followed by saturation at higher fluences inferring therewith the formation of ion tracks. The ion fluence dependent Raman examination was also found to be in line with the XRD observations. However, the presence of Raman modes, characteristic of zirconolite in the 100–1000 cm−1 region, showed intact behavior of the local structure. To sum up, the 120 MeV heavy Au+ ions developed columnar defects, vacancies and induced micro-strains that lead to the bonds distortion and eventually amorphization of the zirconolite though retaining local ordering.

The electrical transport properties of Ti/n-Si Schottky barrier structure irradiated by 100 MeV O7+ ion has been studied between 120 K and 320 K and compared with unirradiated Ti/n-Si structure to gain the understanding of carrier transport mechanism in irradiated devices. The barrier parameters have been extracted using the current-voltage (I–V) characteristics in forwarding bias. It is found that Schottky barrier height (zero bias) increases while the value of ideality factor becomes smaller with increasing temperature. Recent models consisting of inhomogeneous barrier potential at the metal-semiconductor (MS) interface have been used to explain the behavior of barrier parameters. The role played by the high energy ions at MS interface during irradiation is considered to understand the observed behavior.

The nanocomposite thin films of Tin oxide (SnO2) and Titanium dioxide(TiO2) were deposited on silicon and ITO substrate by RF magnetron sputtering technique using sintered pellet formed by mixing S...

Inert matrix fuel concept for minor actinide transmutation proposes stabilized zirconia as the major component for inert matrix. The present study explores Nd-stabilized zirconia (Zr0.8Nd0.2O1.9; Nd as surrogate for Am) and its composites for radiation tolerance against fission fragments. The introduction of MgO in the composite with stabilised zirconia is performed from the point of view to enhance the thermal conductivity. The radiation damage is also compared with Nd-stabilized zirconia co-doped with Y3+ (Zr0.8Nd0.1Y0.1O1.9) in order to mimic doping of minor actinides in Y3+ containing stabilized zirconia (Nd as surrogate for Am). The compositions were synthesized by gel combustion followed by high temperature sintering and characterised by XRD, SEM and EDS. Irradiation was carried out by 120 MeV Au ions at various fluences and irradiation induced structural changes were probed by in-situ X-ray diffraction (XRD). XRD demonstrated the retention of crystallinity for all the three samples but the extent of the damage was found to be highly dependent on the nominal composition. It was observed that introduction of Y3+ along with Nd3+ to stabilize cubic zirconia imparted poorer radiation stability. On the other hand, formation of a CERCER composite of MgO with Nd-stabilised zirconia enhanced its behaviour against swift heavy ion irradiation. Investigating these compositions by XANES spectroscopy post irradiation did not show any change in local electronic structure of constituent ions.

The physical and chemical properties of soft polymer–ceramic composites with 50 MeV swift heavy, Li3+ ion irradiation were studied. A solution-casting technique was employed to synthesize free standing, flexible composite films of ferroelectric polymer PVDF and ferroelectric ceramic BNBT mixtures with 0–3 connectivity. However, only 35 wt% ceramic was chosen for the study as it showed the highest dielectric constant and enhanced ferroelectric properties without irradiation. The effects of ion irradiation on the structural, microstructural, morphological, dielectric and ferroelectric properties of this particular composition were systematically investigated and conclusions were drawn. The mechanism for the enhancement of the electroactive β-phase due to the swift heavy ion irradiation was discussed and the enhancement was well correlated with its ferroelectric and dielectric properties.

The difference in the defect structures produced by different ion masses in a tungsten lattice is investigated using 80 MeV Au7+ ions and 10 MeV B3+ ions. The details of the defects produced by ions in recrystallized tungsten foil samples are studied using transmission electron microscopy. Dislocations of type b = 1/2[111] and [001] were observed in the analysis. While highly energetic gold ion produced small clusters of defects with very few dislocation lines, boron has produced large and sparse clusters with numerous dislocation lines. The difference in the defect structures could be due to the difference in separation between primary knock-on atoms produced by gold and boron ions.

State of the art applications (nuclear waste host, scintillators, piezoelectric, SOFCs, etc.) of isometric pyrochlore, A2B2O7, are very sensitive to the structural assessment upon ion irradiation. In the present study, La2Zr2O7 is irradiated using 1 MeV Xe4+ ions with fluence of 1 × 1013, 5 × 1013, and 1 × 1014 ions/cm2 at ~ 88 K and 300 K. The impact of irradiation temperature and ion fluence on the structural properties of the La2Zr2O7 are investigated using the GIXRD, Raman spectroscopy and high resolution transmission electron microscopy (HR-TEM). The GIXRD and Raman results indicate that the degradation of the crystallinity (i.e., damage/amorphization) are significantly higher with enhanced fluence at ~ 88 K than that of 300 K. The induced lattice strain also increases with an increase of ion fluence and it is more pronounced at ~88 K. The HR-TEM results of the La2Zr2O7 samples exhibit that degradation of the atomic ordering are more pronounced at ~ 88 K. The prominent induced strain and degradation of crystallinity (i.e., damage/amorphization) at ~ 88 K appear to be ion fluence and irradiation temperature-dependent. This study is enlightening the effect of the ion fluence and irradiation temperature on the degradation of crystallinity (i.e., damage/amorphization).

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.

Hydrogen gas sensing response of RF sputtered nano-crystalline ZnO thin film is improved by $\sim 34.73$ % using swift heavy ion irradiation technique. X-ray diffraction reveals single crystalline wurtzite structure of ZnO thin films. Full width half maximum (FWHM) of (0002) diffraction peak is decreased with increase in ion fluences. However, at very high fluence $1\times 10^{13}$ ions/cm2, crystallinity is degraded while FWHM of diffraction peak increases. The ZnO films were grown under highly compressive stress, which was relaxed with incremental ion fluences up to $1\times 10^{13}$ ions/cm2. Cathodoluminenscence spectroscopy shows intense predominant peak around $\sim 3.23$ eV, which indicates good optical quality of the films. As ion fluence increases, a blue shift appears in near band emission peak from 3.23 to 3.33 eV, which indicates that in-plane stress is decreased. Surface morphology shows generation of self-affine nanostructure and grain fragments as ion fluences were increased. Grain fragmentations had enhanced the surface reaction, and as a result, gas sensor’s relative response has improved. It was observed that the gas sensor’s sensitivity is strongly dependent on ion fluences and operating temperature. The sensitivity was enhanced from 66.68% to 89.84% with fluence variations from pristine to $1\times 10^{12}$ ions/cm2 at 175 °C operating temperature.

The immobilization of minor actinides and alkaline-earth metal is a major concern in nuclear industry due to their long-term radioactive contribution to the high level waste (HLW). Materials having zirconolite, pyrochlore, and perovskite structure are promising candidates for immobilization of HLW. The zirconolite which exhibits high radiation stability and corrosion resistance behavior is investigated for its radiation stability against alpha particles in the present study. CaZrTi 2 O 7 pellets prepared using solid state reaction techniques, were irradiated with 30 keV He + ions for the ion fluence varying from 1 × 10 17 to 1 × 10 21 ions/m 2 . Scanning electron microscopy (SEM) images of the un-irradiated sample exhibited well separated grains with average size of about 6.8 μm. On the ion irradiation, value of the average grains size was about 7.1 μm, and change in the microstructure was insignificant. The X-ray photoelectron spectroscopy (XPS) studies showed a shift in the core level peak position (of Ca 2p, Ti 2p and Zr 3d) towards lower binding energy with respect to pristine sample as well as loss of oxygen was also observed for sample irradiated with the ion fluence of 1 × 10 20 ions/m 2 . These indicate a decrease in co-ordination number and the ionic character of M O bond. Moreover, core level XPS signal was not detected for sample irradiated with ion fluence of 1 × 10 21 ions/m 2 , suggesting surface damage of the sample at this ion fluence. However, X-ray diffraction (XRD) studies showed that zirconolite was not amorphized even on irradiation up to a fluence order of 1 × 10 21 ion/m 2 . But, significant decrease in peak intensity due to creation of defects and a marginal positive peak shift due to tensile strain induced by irradiation, were observed. Thus, XRD along with XPS investigation suggests that reduction, decrease in co-ordination number, and increase in covalency are responsible for the radiation damage in zirconolite.

Effect of (80 MeV) 16 O 6 + ion irradiation on the structural properties and cation distribution of the as-burnt samples (i.e. the samples are without any thermal/sintering treatment) with the following compositions: MnFe 2 O 4 , Mn 0.5 Zn 0.5 Fe 2 O 4 and ZnFe 2 O 4 prepared by sol–gel auto-combustion technique have been studied through in-situ and ex-situ X-ray diffraction (XRD) technique. Well characterized single phase MnFe 2 O 4 and Mn 0.5 Zn 0.5 Fe 2 O 4 samples were irradiated at fluence 1 × 10 11 , 1 × 10 12 , 1 × 10 13 and 1 × 10 14 ions/cm 2 to see the effect of the electronic energy loss induced changes in the structural properties and in cation distribution monitored through ex-situ XRD. ZnFe 2 O 4 samples were irradiated with ion fluence values ranging between 1 × 10 11 − 2 × 10 14 ions/cm 2 to observe the effect of in-situ XRD on structural properties and cation distribution. Results very clearly depict the redistribution of cations in the samples, which show noticeable changes in: ionic radii of A-site ( r A ) and B-site ( r B ), experimental and theoretical lattice parameter ( a exp. , a th. ), unit cell volume ( V ), Scherrer’s Grain diameter ( D ), oxygen positional parameter ( u ), tetrahedral and octahedral bond length ( R A , R B ), shared tetrahedral and octahedral edge ( d AE , d BE ) and bond angles ( θ 1 , θ 2 , θ 3 , θ 4 , θ 5 ). Results are interpreted in terms of irradiation induced changes in the above mentioned parameters.

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.

The CdS–Bi2S3 bi-layer thin films have been deposited on Indium Tin Oxide (ITO) glass substrates at room temperature by Chemical Bath Deposition Technique (CBD) and bi-layer thin films were annealed in air atmosphere for 1 h at 250 °C. The air annealed sample was irradiated using Au9+ ions at the fluence 5 × 1011 ion/cm2 with 120 MeV energy. Effects of Swift Heavy Ion (SHI) irradiation on CdS–Bi2S3 bi-layer thin films were studied. The results are explained on the basis annealing and high electronic excitation, using X-ray diffraction (XRD), Selective Electron Area Diffraction (SEAD), Atomic Force Microscopy (AFM), Raman Spectroscopy, UV spectroscopy and I–V characteristics. The photosensing property after illumination of visible light over the samples is studied. These as-deposited, annealed and irradiated bi-layer thin films are used to sense visible light at room temperature.

Solar-blind photodetectors are critically important for civil and military applications. Several of these applications, such as space exploration and nuclear energy infrastructure, demand the use of a photodetector under extreme environments. In this paper, we have studied the radiation hardness and device performance of amorphous and polycrystalline gallium oxide thin films against heavy ion (Ag7+) irradiation with a high energy of 100 MeV. Gallium oxide thin films show great tenacity against massive and highly energetic ions. The amorphous and polycrystalline phases undergo structural and morphological changes that initially induce degradation in the device performance. Nano-pore like structures are formed in the amorphous film, while the polycrystalline film shows the destruction of large crystallites. The responsivity of the photodetector device reduces fourfold in the amorphous phase; however, a sixfold reduction in the performance is observed in the polycrystalline phase of the gallium oxide photodetector. The degradation is attributed to the annealing of pre-existing optical defects that are otherwise responsible for the huge photoconductive gain in the detector and confirmed by photoluminescence studies. The effect of self-annealing at room temperature and annealing at moderate temperature is investigated to recover the irradiated photodetector devices. Partial recovery in the polycrystalline based photodetector and two orders of magnitude enhanced responsivity and an almost twice faster response time compared to the control photodetectors in the amorphous phase are observed. This work investigates the effect of heavy and energetic ions on the performance of gallium oxide based solar-blind photodetector and provides the guideline to use high energy irradiation as a tool for defect engineering.

The understanding of the influence of energetic ions on the transport properties of semiconductor materials is essential to design the devices for use in a radiation environment. In this article, an in-situ investigation of the effect of 100 MeV O7+ irradiation on the current-voltage characteristics of the Pd/n-Si Schottky barrier structure is carried out. It is observed that the interface barrier parameters (Ideality Factor, Schottky barrier height and reverse saturation current) are a strong function of ion fluence. The voltage dependence of conduction mechanisms indicates the presence of defects near the interface as well as in bulk silicon. The energy loss mechanisms of energetic ions in the Pd/n-Si structure are used to explain the observed results after irradiation.

The dependence of radiation stability of Gd 2 Zr 2 O 7 on stoichiometry and structure under swift heavy ion irradiation was investigated. Gd 2 Zr 2 O 7 , lies on the borderline of pyrochlore to fluorite phase transition, hence, it is highly sensitive to variations in the composition and/or synthesis conditions. The Gd 2 Zr 2 O 7 was synthesized in two sets (Set-A and -B) by solid state synthesis and gel combustion yielding different phases and stoichiometry as confirmed by Resonant Rutherford backscattering spectrometry (RRBS) and field emission scanning electron microscopy (FESEM). Both sets of Gd 2 Zr 2 O 7 were irradiated with 120 MeV Au ions with fluences varying from 3×10 11 to 1×10 14 ions/cm 2 . The pristine and irradiated samples were studied by X-ray diffraction (XRD) and Raman spectroscopy. The Set-A sample with pyrochlore structure remained crystalline upto the highest fluence 10 14 ions/cm 2 employed, whereas Set-B sample having anion-deficient fluorite structure lost crystallinity at the fluence of 5×10 13 ions/cm 2 , as revealed by in-situ XRD experiment. The in-situ XRD along with Raman studies elucidated that sample synthesized using solid state reaction process exhibits better stability under swift heavy ion irradiation, implying that the sample with perfect stoichiometric pyrochlore structure possess better radiation stability.

In order to simulate radiation damages in tungsten, potential plasma facing materials in future fusion reactors, surrogate approach of heavy ion irradiation on polycrystalline tungsten is employed. Tungsten specimen is irradiated with gold heavy ions of energy 120 MeV at different fluences. Positron annihilation lifetime measurements are carried out on pristine and ion beam irradiated tungsten specimens. The variation in positron annihilation lifetime in ion irradiated specimens confirms evolution of vacancy clusters under heavy ion irradiation. The pristine and irradiated tungsten specimens have also been characterized for their microstructural, structural, electrical, thermal, and mechanical properties. X-ray diffractograms of irradiated tungsten specimens show structural integrity of polycrystalline tungsten even after irradiation. Nevertheless, the increase in microstrain, electrical resistivity and microhardness on irradiation indicates creation of lattice damages inside polycrystalline tungsten specimen. On the other hand, the thermal diffusivity has not change much on heavy ion irradiation. The induction of damages in metallic tungsten is mainly attributed to high electronic energy loss, which is 40 keV/nm in present case as obtained from SRIM program. Although, concomitant effect of nuclear losses on damage creation cannot be ignored. It is believed that the energy received by the electronic system is being transferred to the atomic system by electron-phonon coupling. Eventually, elastic nuclear collisions and the transfer of energy from electronic to atomic system via inelastic collision is leading to significant defect generation in tungsten lattice.

CdS–Bi2S3 bi-layer thin films have been deposited by chemical bath deposition method on Indium Tin Oxide glass substrate at room temperature. The as-deposited thin films were annealed at 250 °C in an air atmosphere for 1 h. An air annealed thin film was irradiated using Au9+ ions with the energy of 120 MeV at fluence 5×1012 ions/cm2 using tandem pelletron accelerator. The irradiation induced modifications were studied using X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Raman spectroscopy, UV spectroscopy and I–V characteristics. XRD study reveals that the as-deposited thin films were nanocrystalline in nature. The decrease in crystallite size, increase in energy band gap and resistivity were observed after irradiation. Results are explained on the basis of energy deposited by the electronic loss after irradiation. The comparative results of as-deposited, air annealed and irradiated CdS–Bi2S3 bi-layer thin films are presented.

An in-situ high temperature (1000 K) setup is designed and installed in the materials science beam line of superconducting linear accelerator at the Inter-University Accelerator Centre (IUAC) for temperature dependent ion irradiation studies on the materials exposed with swift heavy ion (SHI) irradiation. The Gd 2 Ti 2 O 7 pyrochlore is irradiated using 120 MeV Au ion at 1000 K using the high temperature irradiation facility and characterized by ex-situ X-ray diffraction (XRD). Another set of Gd 2 Ti 2 O 7 samples are irradiated with the same ion beam parameter at 300 K and simultaneously characterized using in-situ XRD available in same beam line. The XRD studies along with the Raman spectroscopic investigations reveal that the structural modification induced by the ion irradiation is strongly dependent on the temperature of the sample. The Gd 2 Ti 2 O 7 is readily amorphized at an ion fluence 6 × 10 12 ions/cm 2 on irradiation at 300 K, whereas it is transformed to a radiation-resistant anion-deficient fluorite structure on high temperature irradiation, that amorphized at ion fluence higher than 1 × 10 13 ions/cm 2 . The temperature dependent ion irradiation studies showed that the ion fluence required to cause amorphization at 1000 K irradiation is significantly higher than that required at room temperature irradiation. In addition to testing the efficiency of the in-situ high temperature irradiation facility, the present study establishes that the radiation stability of the pyrochlore is enhanced at higher temperatures.

This paper reports an unusual extent of mixing in Bi/Te thin bilayer system using 90 MeV Au and 95 MeV Ag ions of energies having same electronic energy loss (S e ) value. The analysis is made using Rutherford backscattering spectroscopy and atomic force microscopy. The mixing variance as observed from the depth profiles extracted from RBS data using Rutherford universal manipulation program is found to be higher for Au irradiated samples. Similarly higher sputtering yield is observed for Au ions than Ag ions. These have been accounted to ion velocity effect of Bi/Te with Au ions having velocity ~1.3 times slower to Ag ions.

MeV Ag ions have been used to study the swift heavy ion (SHI) induced modification in Te/Bi bilayer system. The samples were analysed using Rutherford backscattering spectroscopy (RBS), Atomic force microscopy (AFM) and X-ray diffractometer (XRD). The elemental depth study with RBS results show a strong mixing between the top Te layer and the underlying Bi layer on irradiation. Surface roughness as calculated by AFM is found to increase from 8 to 30 nm on irradiation for the fluence 3x10 13 ions/cm 2 . XRD results confirm the formation of Bi-Te alloy phases on mixing and are expected to be formed due to the interfacial reaction taking place within the molten ion tracks. Ion beam mixing has the potential to induce the formation Bi-Te alloy thin films which are the promising candidate for thermoelectric applications near room temperature. Copyright © 2014 VBRI press.

The Al-induced crystallization of amorphous (a)-Si under thermal annealing and swift heavy ion irradiation has been investigated. The c-Al (50 nm)/a-Si (150 nm) thin films have been prepared on thermally oxidized Si-substrates. A set of samples have been annealed at temperatures ranging from 100 °C to 500 °C to achieve crystallization. Another set of similar samples have been irradiated at an elevated temperature of 100 °C using 100 MeV Ni+7 ions at fluences of 1 × 1012 ions-cm−2, 5 × 1012 ions-cm−2, 1 × 1013 ions-cm−2, and 5 × 1013 ions-cm−2. The crystallization of a-Si is observed at annealing temperature of 200 °C. The crystallinity increases with increasing temperature. On the other hand, irradiation using swift heavy ion leads to crystallization of a-Si at significantly lower temperature of 100 °C. The irradiation induced crystallization is explained in terms of creation of vacancies, interstitials and mixing of Si and Al atoms at a-Si/c-metal interface due to energy deposited by swift Ni ions.

The pyrochlore structure is of particular interest to the nuclear industry due to its potential for nuclear waste immobilization and as a host material for inert matrix fuels. Herein, the experimental results of the temperature and ion fluence dependence on the disordered ion tracks produced by the electronic excitation in the pyrochlore compound Nd2Zr2O7 are presented. The samples were exposed to extreme conditions of ion irradiation with 100 MeV 107Ag9+ ions at ion fluences ranging from 3 × 1011 ions/cm2 to 2 × 1013 ions/cm2 at temperatures of 300 K and 1000 K. The in-situ X-ray diffraction along with micro-Raman spectroscopic analysis on Nd2Zr2O7 samples irradiated at 300 K displays order-disorder phase transformation which is consistent with earlier reports. The direct-impact model is used to calculate the amorphous fraction which exists due to massive deposition of electronic-energy in a localized region, and the estimated value of track radius is 2.98 ± 0.56 nm. Furthermore, theoretical thermal spike simulations are performed to estimate the track radius (∼4.2 nm) which provides strong support for experimental results. To simulate the response of Nd2Zr2O7 under nuclear reactor environment, irradiation carried out at an elevated temperature that exhibits significant radiation tolerance. Its substantiality is revealed from comparative temperature dependent irradiation studies where a slow rate of amorphization is found at the elevated temperature because of the competition between defect production and thermal healing mechanism. Thus, obtained results strongly endorse the appositeness of Nd2Zr2O7 as inert matrix material for the fabrication of futuristic nuclear fuel.

Yttria stabilized zirconia pellets with different crystallite sizes were irradiated with 80 MeV Ag6+ ions at room temperature and 1000 K to understand the effect of crystallite size/material microstructure and irradiation temperature on the radiation tolerance against high energy heavy ions [where electronic energy loss (Se) dominates]. XRD and Raman spectroscopy measurements reveal that, irrespective of the irradiation temperature, the nano-crystalline samples suffered more damage when compared with the bulk-like sample. A reduction in the irradiation damage, i.e., improvement in the radiation tolerance, was observed for all the samples irradiated at 1000 K. The reduction in the damage, however, was remarkably higher for the nano-crystalline samples compared with the bulk-like sample, and hence the difference in the damage between the bulk-like and nano-crystalline samples was also significantly lower at 1000 K than that at room temperature. The irradiation damage, against Se, was thus found to be critically dependent on the interplay between the irradiation temperature and the crystallite size. These results are explained on the basis of the “in-elastic thermal spike” model by taking into consideration the combined effects of crystallite size and environmental (irradiation) temperature on the electron-phonon coupling strength and the lattice thermal conductivity and hence on the resulting thermal spike. These results, besides being crucial from the fundamental prospect of comprehending the size and temperature dependent radiation damage against Se, may also be important from the perspective of designing highly nano-crystalline materials for applications in various radiation environments.

We report on the effect of 80 keV Xe+ ion irradiation on the commercially available, sectioned 10B pencil-graphite specimens subjected to normal and oblique angle incidence of ions (θ i = 0°–70°) and considering a fixed ion fluence of . The pristine and irradiated samples were characterized by powder x-ray diffraction, atomic force microscopy and Raman spectroscopy studies. Unlike pristine graphite and normal incidence cases, several ripple patterns can be visualized in the atomic force micrographs of the specimens irradiated with an oblique angle incidence. Moreover, apart from conventional G-band located at , a distinct diamond-like carbon (DLC) phase has been witnessed at in the Raman spectra of the graphitic specimens subjected to ion impact and for values of 50° and 70°. The formation of the DLC phase along with surface ripple formation would find numerous scopes while dealing with properties such as surface transport, field emission and mechanically hard coating in miniaturized devices.

Hydroxyapatite (HAp, Ca10(PO4)6(OH)2) is the main inorganic component of hard tissues like bone and teeth. HAp incorporated with magnetic ions, play an important role in cell separation, magnetic resonance imaging (MRI), targeted drug delivery and in hyperthermia treatment of cancer. In this study, the effect of 60 MeV Si 5+ ion on the hydrothermally synthesized Fe 3+ doped hydroxyapatite (Fe-HAp, 33 nm) was investigated. At higher fluences, partial amorphization with an increase in the cluster size and surface roughness was observed. Depending on the ion fluence, pores ranging from 300 to 360 nm in size were produced. Irradiated Fe-HAp samples showed enhanced haemocompatibility and bioactivity. The drug (amoxycillin, AMX) loaded irradiated samples exhibited high antimicrobial activity. Copyright © 2013 VBRI press.

The effect of swift heavy 100 MeV Ag7+ ions irradiation was studied on hydroxyapatite (HAp) thin film prepared by pulsed laser deposition technique (PLD). The GIXRD analysis confirmed the absence of any phase in the HAp phase due to irradiation. In addition, there was a considerable decrease in crystallinity and crystallite size on irradiation. There was no significant variation in the stoichiometry of the irradiated films. Irradiation seemed to decrease the optical band gap energy of HAp thin films. The surface roughness, wettability and bioactivity were improved on irradiation of the samples. Amount of amoxicillin loading/release increased (10%) in ion beam irradiated (1 × 1012 ions cm−2) sample. Irradiated sample showed fast rate of amoxicillin (AMX) release than the pristine. Bactericidal effect was found to increase on irradiation. Surface modified and antibiotics incorporated HAp coated titanium implants may be used to prevent post-surgical infections and to promote bone-bonding of orthopedic devices.

We have investigated neutron irradiation effects on the optical, structural and chemical properties of polyallyl diglycol carbonate (PADC) polymer, commercially named as CR-39. For this purpose, PADC samples were exposed with 4 MeV Am–Be neutron source at fluences varying from 2.36 × 10 6 to 5.94 × 10 7 n/cm 2 . The modifications so induced were analyzed using UV–Visible spectroscopy, X-ray diffraction Measurement (XRD), Photoluminescence (PL) and Fourier Transform infrared (FTIR) spectroscopy in the total attenuation reflection (ATR) mode. UV–Vis spectra of pristine and neutron irradiated PADC polymer sheets exhibit a decreasing trend in optical band gap. This decline in optical band gap with increasing fluence has been discussed on the basis of neutron irradiation induced defects in PADC. The XRD pattern of PADC shows the decreasing intensity of peak positions with increasing in fluence, which suggest that semicrystallinity of PADC changes slightly to amorphous phase after irradiation. At low fluence, crystallinity was found to increase but at higher fluence, it decreased which could be ascribed to neutron- induced defects in the polymer samples. Crystallite size calculated using Scherrer formula indicates a change and reflects the formation of disordered system in the irradiated polymer samples. The PL spectra show that the intensity of PL peak decreased with increase in fluence, which may be due to the disordered system via creation of defects in the irradiated polymer. The FTIR spectrum shows an overall reduction in intensity of the typical bands, indicating the degradation of PADC polymer after irradiation. These results so obtained can be used successfully in dosimetery using well reported protocols.

Our long term objective is to study the swift heavy ion (SHI) irradiation effect on photoanode of dye-sensitized solar cell (DSSC) with the aim to investigate the stability of DSSC component in space irradiations and possibility of improvement in efficiency of DSSC due to ion induced effects in oxide layer. The DSSC photoanode consists of three layers viz; transparent conducting oxide (TCO), porous oxide with wide band gap and monolayer of dye molecule on top of corning glass substrate respectively. In the present study, procured radio frequency (RF) sputtered indium tin oxide (ITO) film on corning glass substrate were irradiated by SHI using 110 MeV Ni8+ ions at different fluences ranging from 3.0 × 1011 ion/cm2 to 1.0 × 1014 ion/cm2. After irradiation significant changes have been observed in the structural, optical and electrical properties using X-ray diffraction (XRD), UV–Vis and Four Probe measurements, respectively. Overall there is 13% increase in optical transmittance which is favorable and moderate increase in sheet resistance from 8 Ω/□ to 18 Ω/□ which is still within acceptable limits for DSSC applications.

This paper reports the effect of the irradiation of 50 MeV Li+3 ions on the thermomechanical properties of PMMA/PC blends. The radiation has been carried out at fluences of 1010 to 1012 ions/cm2 to observe any kind of chain scissoring/crosslinking occurring in the sample. The irradiated as well as the pristine samples have been characterized using X-ray diffraction (XRD), Fourier transform spectroscopy (FTIR), scanning electron microscopy (SEM) and dynamic mechanical analyzer (DMA) to study the induced changes in the structural, morphological and mechanical properties in blend films. The XRD results show an increase in the degree of crystallinity upon ion irradiation at low fluences (≤1011 ions/cm2) and a decrease in crystallinity at high fluences (>1011 ions/cm2), while the FTIR spectra show no appreciable change after irradiation. The mechanical characterization reveals that radiation significantly modifies the mechanical properties and the glass transition temperature of these polymeric blends.

Swift Heavy Ion (SHI) irradiation of the polymeric materials modifies their physico-chemical properties. Lexan polycarbonate films were irradiated with 95 MeV oxygen ions to the fluences of 1010, 1011, 1012, 1013 and 2 × 1013 ions/cm2. Characterization of optical, chemical, electrical and structural modifications were carried out by UV–Vis spectroscopy, FTIR spectroscopy, Dielectric measurements and X-ray Diffraction. A shift in the optical absorption edge towards the red end of the spectrum was observed with the increase in ion fluence. The optical band gap (Eg), calculated from the absorption edge of the UV–Vis spectra of these films in 200–800 nm region varied from 4.12 eV to 2.34 eV for virgin and irradiated samples. The cluster size varied in a range of 69–215 carbon atoms per cluster. In FTIR spectra, appreciable modification in terms of breaking of the cleavaged C–O bond of carbonate and formation of phenolic O–H bond was observed on irradiation. A rapidly decreasing trend in dielectric constant is observed at lower frequencies. The dielectric constant increases with fluence. It is observed that the loss factor increases moderately with fluence and it may be due to scissoring of polymer chains, resulting in an increase in free radicals. A sharp increase in A.C. conductivity in pristine as well as in irradiated samples is observed with frequency and is attributed to scissoring of polymer chains. XRD analyses show significant change in crystallinity with fluence. A decrease of ∼9.02% in crystallite size of irradiated sample at the fluence of 2 × 1013 ions/cm2 is observed.

In this study, composite films consisting of an insulating polymethyl methacrylate (PMMA) polymer matrix and metal powder (Cu) additive were prepared by solution costing method. These films were irradiated with 140 MeV silver ions at the fluences of 1 × 1011 ions/cm2 and 1 × 1012 ions/cm2. The radiation induced changes in dielectric, structural and surface properties of PMMA/Cu composites were studied using impedance/gain phase-analyzer, X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). It was observed that the dielectric properties and ac electrical conductivity increased significantly with the concentration of dispersed metal powder (Cu) and also with the fluence. This reveals that ion beam irradiation creates free radicals, unsaturation etc. due to emission of hydrogen and/or other volatile gases, which makes the polymer more conductive. XRD analysis of the pristine and irradiated samples shows that the crystallinity improved upon irradiation at low fluence and deteriorated on further increase of the fluence, which could be attributed to cross linking of polymer chains at low fluence and degradation at higher fluence. High energy ion beam irradiation of semicrystalline polymer composite films changes its Tg behavior as observed from DSC analysis. This result is also corroborated with the results of XRD. The average surface roughness and topography of surfaces changed with the concentration of filler and also with the ion fluence as revealed from AFM/SEM analysis.

Poly(vinylidene fluoride-co-hexafluoropropylene) (HFP) nanocomposites with layered silicate have been synthesized via the melt extrusion route. The intriguing nanostructure, crystalline structure, morphology, and thermal and mechanical properties of the nanocomposites have been studied and compared critically with pristine polymer. HFP forms intercalated or partially exfoliated nanostructure (or both) in the presence of nanoclay, depending on its concentration. The bombardment of high-energy swift, heavy ions (SHI) on HFP and its nanocomposites has been explored in a wide range of fluence. The nanoclay induces the piezoelectric beta-phase in bulk HFP, and the structure remains intact upon SHI irradiation. SHI irradiation degrades pure polymer, but the degradation is suppressed radically in nanocomposites. The heat of fusion of pristine HFP has drastically been reduced upon SHI irradiation, whereas there are relatively minute changes in nanocomposites. The coarsening on the surface and bulk of HFP and its nanocomposite films upon SHI irradiation has been measured quantitatively by using atomic force microscopy. The degradation has been considerably suppressed in nanocomposites through cross-linking of polymer chains, providing a suitable high-energy, radiation-resistant polymeric material. A mechanism for this behavior originating from the swelling test and gel fraction (chemical cross-linking) as a result of SHI irradiation has been illustrated.

CdTe polycrystalline thin films possessing hexagonal phase regions are obtained by spray deposition in presence of a high electric field. Thin film samples are irradiated with 100 MeV Ag ions using Pelletron accelerator to study the swift heavy ion induced effects. The ion irradiation results in the transformation of the metastable hexagonal regions in the films to stable cubic phase due to the dense electronic excitations induced by beam irradiation. The phase transformation is seen from the X-ray diffraction patterns. The band gap of the CdTe film changes marginally due to ion irradiation induced phase transformation. The value changes from 1.47 eV for the as deposited sample to 1.44 eV for the sample irradiated at the fluence 1 × 10 13 ions/cm2. The AFM images show a gradual change in the shape of the particles from rod shape to nearly spherical ones after irradiation.

High-energy ion beam irradiation of the polymers is a good technique to modify the properties such as electrical conductivity, structural behaviour and mechanial properties. Polyaniline thin films doped with hydrochloric acid (HCl) were prepared by oxidation of ammonium persulphate. The effect of Swift Heavy Ions irradiation on the electrical and structural properties of polyaniline has been measured in this study. Polyaniline films were irradiated by oxygen ions (energy 80 MeV, charge state O+7) with fluence varying from 1 × 1010 to 3 × 1012 ions/cm2. The studies on electrical and structural properties of the irradiated polymers were investigated by measuring V-I using four probe set-up and X-ray diffraction (XRD) using Bruker AXS, X-ray powder diffractometer. V-I measurements shows an increase in the conductivity of the film, XRD pattern of the polymer shows that the crystallinity improved after the irradiation with Swift Heavy Ions (SHI), which could be attributed to cross linking mechanism.

Polymethyl methacrylate (PMMA) was synthesized by solution polymerization technique. Different concentrations of organometallic compound/palladium (II) acetylacetonate [Pd(acac)] were dispersed in PMMA. The composite films were irradiated with 3 MeV proton beam at a fluence of 10 13 ions/cm 2 . The radiation induced changes in structural and chemical properties were studied by means of X-ray diffraction (XRD) and FTIR spectroscopy. The XRD results reveal that the crystalline size and crystallinity of the composite films decrease after irradiation, however crystallinity increases with filler concentration. This is due to the crystalline behavior of Pd(acac). Fourier transform infrared spectroscopy has been studied in transmittance mode. The decrement in the peak intensity is attributed to chain scissioning of the polymeric bonds. Chain scissioning is also responsible for the decrement in the crystallinity of the composites. The glass transition temperature was observed to decrease after irradiation as revealed from differential scanning calorimetry (DSC) thermograms. Scanning electron microscopy (SEM) reveals that the surface roughness increases due to irradiation.

Commercially purchased CR-39 and PET polymers were irradiated by 100 MeV O7+ ions of varying fluences, ranging from 1×1011 to 1×1013 ions/cm2. The effects of swift heavy ions (SHI) on the structural, optical and chemical properties of CR-39 and PET polymers were studied using X-ray diffraction (XRD), UV–visible spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The XRD patterns of CR-39 show that the intensity of the peak decreases with increasing ion fluence, which indicates that the semicrystalline structure of polymer changes to amorphous with increasing fluences. The XRD patterns of PET show a slight increase in the intensity of the peaks, indicating an increase in the crystallinity. The UV–visible spectra show the shift in the absorbance edge towards the higher wavelength, indicating the change in band gap. Band gap in PET and CR-39 found to be decrease from 3.87 to 2.91 and 5.3–3.5 eV, respectively. The cluster size also shows a variation in the carbon atoms per cluster that varies from 42 to 96 in CR-39 and from 78 to 139 in PET. The FTIR spectra show an overall reduction in intensity of the typical bands, indicating the degradation of polymers after irradiation.

Poly(vinylidene fluoride) (PVDF) has been made radiation-resistant through a nanocomposite (NC) route. The bombardment of high-energy swift heavy ions (SHI) on PVDF and its NCs with layered silicate has been studied in a range of fluences. The degradation of PVDF after SHI irradiation is suppressed radically in NCs. PVDF forms an intercalated nanostructure in the presence of nanoclay and, further, the ion fluence raises the extent of intercalation. The crystallinity and the heat of fusion of pristine PVDF have drastically been reduced after SHI irradiation, while there are relatively small changes in NCs even at higher fluences. The metastable piezoelectric beta form of PVDF gets stabilized by the presence of layered silicate, and the structure is retained upon SHI irradiation. The clay platelets act as nucleating agents, and SHI irradiation causes two crystallization temperatures for the samples exposed to high fluences. The damages created on the surface and bulk of PVDF and its NC films upon SHI irradiation have been measured quantitatively by using atomic force microscopy. The pitting dimensions and degradation are enhanced significantly beyond 10(11) ions/cm(2) fluence for pristine PVDF, which limits the use of PVDF for any ion irradiation application. The degradation is considerably suppressed in NCs, providing a suitable high-energy radiation-resistant thermoplastic polymer.

Poly(m-toluidine) (PmT) and Poly(o-toluidine) (PoT) have been synthesized from derivatives of aniline (m-toluidine), (o-toluidine) monomers by chemical oxidative polymerization method. After polymerization, PoT powder was doped with p-toluene sulphonic acid (p-TSA) and the polymer powders were blended with poly vinyl chloride (PVC) to achieve PmT and p-TSA doped PoT dispersed films. XRD, FTIR and UV–visible studies were carried out to get their structural changes and optical information. These blends were irradiated by 60 MeV C5+ ions with different fluences. Post Irradiation XRD, FTIR and UV–visible spectroscopy were also performed on all films. On p-TSA doped PoT–PVC blends dc-conductivity measurements are also carried out before and after irradiation. The results show structural modifications which lead to changes in optical and electrical properties.

The films of polymethyl methacrylate (PMMA) were synthesized by solution polymerization technique. Nickel dimethylglyoxime (Ni-DMG) compound was dispersed in polymethyl methacrylate (PMMA) films at different concentrations. These films were irradiated with 120 MeV Ni10+ ions at the fluences of 1 × 1011 and 1 × 1012 ions/cm2. These irradiated films were characterized by means of X-ray diffraction (XRD), Vickers’ microhardness tester, atomic force microscopy (AFM) and scanning electron microscopy (SEM). X-ray diffraction patterns revealed that the particle size of Ni-DMG nanoparticles is reduced upon irradiation. It indicates that there is a significant interaction of ion beam with Ni-DMG particles in polymer matrix which leads to deposition of large amount of energy and resulted in splitting/melting of nanometric grains. It also revealed that semi crystalline phase of pristine films has been changed with respect to concentration and with the fluence. It is observed that the hardness of the film increases as fluence increases. This suggests that ion beam irradiation promotes (i) the metal to polymer bonding (ii) convert the polymeric structure in to hydrogen depleted carbon network due to the emission of hydrogen gas and/or other volatile gases. The surface average roughness increases as concentration of filler increases and decreases due to ion beam irradiation as revealed from AFM studies. SEM micrographs show partial agglomeration of filler and flake-like structure upon irradiation.

The induced damage in single crystals of Sodium sulphanilate dihydrate (SSDH) irradiated at IUAC, New Delhi with 15 MV Pelletron accelerator with 100 MeV Ag7+ and 70 MeV Li3+ ions has been studied by optical measurements, mechanical hardness measurements, Electrical and ERDA measurements. Optical absorption measurements increase with the increase in fluence. The mechanical hardness of the crystal decreases on irradiation. The dielectric constant of SSDH increases on irradiation.

The effect of swift heavy ion irradiation on hydroxyapatite (HAp) ceramic – a bone mineral was investigated. The irradiation experiment was conducted using oxygen ions at energy of 100 MeV with three different fluences of 10 12 , 10 13 , 10 14 ions/cm 2 . The irradiated samples were characterized by glancing angle X-ray diffraction (GXRD), atomic force microscopy (AFM), dynamic light scattering (DLS), photoluminescence spectroscopy (PL), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). GXRD confirmed incomplete amorphisation of HAp with increase in fluence. There was considerable reduction in particle size on irradiation leading to nanosized HAp (upto 53 nm). PL studies showed emission in the visible wavelength region. The irradiated samples exhibited better bioactivity than the pristine HAp.

Polymethyl methacrylate (PMMA) was synthesized by solution polymerization technique. Films of polymer composites were prepared by dispersion of different concentrations of nickel dimethylglyoxime in PMMA. These films were irradiated with 3 MeV proton beam at a dose of 1.48×105 Gy. The dielectric, structural properties and surface morphology of pristine and irradiated samples were studied by means of an LCR meter, X-ray diffraction (XRD) analysis and atomic force microscopy (AFM), respectively. The dielectric properties are observed to enhance with increase in metal compound concentration as well as with irradiation dose. This may be due to metal/polymer bonding and conversion of polymeric structure into hydrogen-depleted carbon network. AFM shows that the surface average roughness decreases after irradiation. Crystallite size of organometallic compound is observed to decrease after irradiation as revealed from XRD analysis.

Poly (o-toluidine) was synthesized from a derivative of aniline (o-toluidine) monomer by chemical oxidative polymerization method. After polymerization, the polymer prepared was blended with poly vinyl chloride and irradiated by 60-MeV C5+ ions at five different fluences of 1×1011, 3.3×1011, 1×1012, 3.3×1012 and 1×1013 ions/cm2. The swift heavy ion irradiation effects on crystallinity and DC conductivity were studied. X-ray diffraction study showed variations in crystallinity of the blend films upon irradiation. The crystallinity, DC conductivity and activation energy were found to vary discontinuously with fluence. The DC conductivity and activation energy were obeying Meyer–Neldel rule.