[en] Nanostructures contribute vital applications for surface-based science including latent fingerprints (LFPs) detection and reconstruction. Fingerprints are unique to an individual, matching the finger prints help to identify culprits. Vanadium Pentoxide (V₂O₅) nanorods were synthesized via hydrothermal method using pomegranate peel extract as fuel, towards their use in fingerprint development. PXRD patterns confirmed the formation of orthorhombic V₂O₅ crystal structure. Raman vibration modes at 144 cm⁻¹ and 994 cm⁻¹ signifies the characteristic orthorhombic V₂O₅ structural formation, FTIR spectra shows vibration bands of V₂O₅, UV–vis spectroscopy shows an intrinsic absorption band at ∼418 nm corresponding to electron transitions (O_2p → V_3d). The energy band gap (E_g) estimated from absorption spectrum was found to be ∼2.35 eV. Formation of nanorods was observed from SEM micrographs and particle size was found to be 30 nm from TEM images. Photoluminescence emission studies were performed and yellow –orange (brown) emission was observed from CIE diagram. The characteristic brown/Yellow-orange color of V₂O₅ nanorods supports tracing of LFPs on many kind of surfaces in visible light which eliminates the need for illuminating source. Hence, V₂O₅ nanorods find potential application in Forensic sciences. (paper)

[en] Bougainvillea flower extract was used as a fuel in solution combustion synthesis of pure and Nd³⁺ (1–9 mol %) doped vanadium pentoxides (V₂O₅) nanostructure. Powder x-ray Diffractogram, Scanning electron microscopy and Transmission electron microscopy images revealed the orthorhombic phase in Nd³⁺ doped V₂O₅ nanostructure. The additional peaks in Fourier Transform Infrared spectra and in Raman spectra were due to lattice distortion and mixed valence oxide in VO₄ led to structural and morphological changes. The synthesized Nd³⁺ doped V₂O₅ nanostructure exhibited good photocatalytic activity for the degradation of Methylene blue dye due to decrease in its work function as well as decrease in electron-hole recombination. (paper)

[en] The in situ gamma ray-assisted diffusion of gold nanoparticles in a polycarbonate film modified the nano-structural and surface properties to enable control of functional use with decreases in the free volume nano-hole size and in the fractional free volume measured using positron annihilation lifetime spectroscopic techniques. Coincidenace Doppler broadened spectra showed the identifiable spreading of the gold broadened region of the intensity ratio relative to the pristine polycarbonate film. These results were further corroborated by x-ray photoelectron spectroscopy and Transmission electron microscopy which showed the diffused gold nanoparticles had an average size of about 8 nm, and also showed the bonding of gold nanoparticles with the oxygen functional groups of polycarbonate film. (paper)

[en] Ionoluminescence (IL), photoluminescence (PL) and thermoluminescence (TL) studies of YAlO_3:Tb"3"+, Tm"3"+ (1 at %) single crystals are carried out using 100 MeV Si"7"+ ions for the fluence 3.91 × 10"1"2 ions cm"−"2. IL peaks are recorded in the range 385–450, 493, 544, 585 and 624 nm in Tb"3"+- and 353, 459, 523, 651 and 763 nm in Tm"3"+-doped YAlO_3 single crystals, respectively. PL studies also show similar characteristic emission peaks. The variation of IL intensity is studied in a YAlO_3:Tb"3"+ crystal for a wide fluence range of 3.91 × 10"1"2 –17.57 × 10"1"2 ions cm"−"2. The IL intensity is found to be higher in lower ion fluences, and it decreases with the increase of ion fluence. Thermoluminescence (TL) studies are carried out for ion fluence– (3.91 × 10"1"2 ions cm"−"2) and UV-exposed (05–60 min) single crystals. A single well-resolved glow peak at 242 °C, along with a shouldered peak at 272 °C, is recorded in the Tm"3"+-doped sample. In the Tb"3"+-doped samples, a well-resolved glow peak at 218 °C, along with a shouldered peak at 147 °C, is recorded at the lower temperature side. In the UV-exposed crystals, two glow peaks at 168 °C and 223 °C are recorded. The glow peaks are found to be shifted towards the lower temperature side with an increase in UV exposure time. Good linearity over a large span of UV exposure time and a single glow peak with a simple trap distribution are observed in YAlO_3:Tb"3"+ single crystals, which makes them suitable as a dosimeter for UV-rays. The kinetic parameters (E, b, s) are estimated using the glow peak shape method for both ion and UV-exposed crystals, and the results are discussed in detail. (papers)