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In the present report a sequence of Eu3+ (1-9 mol%) incorporated Mg2SiO2 nanopowders (NPs) are prepared through green mediated Sonochemical synthesis by means of Aloe vera gel as surfactant. Powder X-ray diffraction (PXRD) patterns are studied in order to authorize the phase transparency of the fabricated samples. The PXRD profiles displayed that the fabricated samples have orthorhombic phase [JCPDS Card No. 78-1371] with a space group Pb nm – 62, with no change in the diffraction profiles due to the addition of the Eu3+ ions. The photometric diagrams demonstrate wide excitation and a few sharp peaks. The sharp tops at 360, 375, 381, 393 and 413/362, 373, 381, 450 and 464 nm were 7F0 →5H6, 7D4, 5L7, 5L6 and 5D3 f-f transitions of Eu3+ particles individually. The emission diagram comprise sharp and exceptional peaks situated at ∼590, 612, 652 and 700 nm and was because of the 5D0 → 7FJ (J= 1, 2, 3, 4) advances of 4F6 setup of Eu3+ particles, separately. The CIE arranges (x, y) are resolved (x=0.55, y=0.43) for Mg2SiO4:Eu3+ (5 mol %) relate red emanation which are practically close of the Standard qualities (x=0.67, y=0.33), the Correlated Color Temperature (CCT) was obtained 1992K. We successfully demonstrate the synthesized nanophosphor engaged as a labeling agent to enhance LFPs on different infiltrate and non-infiltrating surfaces. These results indicated that the prepared NPs can be effectively employed in the field of wLEDs and latent finger print detection.

In present work, novel Mg2SiO4: Eu3+ Nanophosphors were blended by sonochemical route utilizing Aloe-Vera gel (A.V.) as bio-surfactant. Crystallinity was studied utilizing PXRD. Scanning Electron magnifying instrument was utilized to concentrate surface changes watched and found that they are varies with concentration of AV gel and sonication control. Photometric investigations reveal that the present nanophosphor transmit solid red color.

In the present communication, various fluxes blended Y2O3:Eu3+ (5 mol%) nanopowders (NPs) were successfully fabricated by solution combustion method. PXRD pattern confirms body-centered cubic structure of the prepared samples. Energy band gap (Eg) of the fabricated products was estimated and is found to be in the range of 3.13–3.32 eV. Photoluminescence (PL) emission spectra exhibit sharp and intense peaks at ∼579, 592, 614, 657, 704 nm corresponding to 5D0 → 7FJ (J = 0, 1, 2, 3 and 4) transitions of Eu3+ ions. Significance of fluxes for enhancing the PL emissions was extensively studied. Photometric studies of the prepared samples are located in pure red region. Optimized NPs were explored as a novel sensing agent for visualization of latent fingerprints (LFPs) on various surfaces including porous, semi-porous and non-porous surfaces followed by powder dusting technique. Various experiments including aging, temperature, scratching and aquatic fresh water treatment tests were performed to evaluate applicability of the fabricated NPs. Visualized LFPs exhibit well defined ridge details including most authenticated sweat pores are also revealed with high sensitivity, selectivity, little background hindrance and less toxicity. Aforementioned results evidence that the method and fabricated NPs can be considered to be simple, rapid and economical and provide novel sensing platform for LFPs visualization in prospective forensic applications.

For the first time green route was used to synthesize pure and Cr3+ (1-11 mol %) doped Yttrium oxide (Y2O3) nanostructures by using Cymbopogon citrates extract as a fuel. The prepared samples were well characterized by powder X-ray diffraction (PXRD), scanning electron microscopy, transmission electron microscopy, Diffused reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The PXRD results shows the formation of single phase, cubic structure of Y2O3 with crystallite sizes ∼15 nm which was further confirmed by TEM results. The SEM results indicated various shaped nanostructures which solely dependent on the fuel concentration. The band gap energy was estimated by DRS and found to be in the range of 5.67 – 5.80 eV. PL results indicate intense sharp peak at ∼ 689 nm along with vibronic side bands 706 and 734 nm. The 689 nm peak was well known R – line and was assigned to the 2Eg → 4A2g transition of Cr3+ions.The CIE (Commission International de I'E' clairage) chromaticity coordinates were located in pure orange- red region. Further, (Commission International de I'E' clairage) CCT values were in the range 3387 – 3486 K. The studies indicate that Y2O3:Cr3+nanophosphors (NPs) were quite useful for display devices

Facile solution combustion route was used to prepare the optimized composite core shell SiO2@Y2O3:Eu3+, Li+ fluorescent nanopowders (NPs) with superior fluorescence intensity under UV light. Powder dusting technique was used for the visualization of latent fingerprints (LFPs) on different porous and non-porous surfaces. The results display that the amorphous SiO2 microspheres were covered by crystalline Y2O3:Eu3+, Li+ NPs, resulting in spherical core-shell structure. The phosphors exhibit intense pure strong red emission corresponding to characteristic Eu3+ ions 5D0→ 7F2 transitions under NUV excitation. The CIE co-ordinates were found to be (x = 0.63, y = 0.36) which is very close to standard NTSC values (x = 0.67, y = 0.33). Judd-Ofelt theory was used to estimate the intensity parameters (Ω2 and Ω4) as well as radiative properties. The CCT value was ∼ 3475 K which was less than 5000 K, as a result the phosphor was highly useful in warm light emitting diodes. Thus, results presented confirms that the developed method was simple, fast and optimized phosphor was effectively used for multifunctional applications namely luminescent sensor for visualization of LFPs, solid state lightning and security ink applications.

Synthesis of Eu 3+ doped Y 2 O 3 nanophosphors via modified sonochemical method was presented. Morphologies of the prepared products were analyzed with respect to the influential parameters during the preparation time. The photoluminescence (PL) emission spectra exhibits several peaks at ∼537 nm, 598 nm, 613 nm and 662 nm attributed to 5 D 0 → 7 F J ( J = 0, 1–3) transitions of Eu 3+ ions in the host lattice. The types of energy transfer between the Eu 3+ ions were responsible for concentration quenching confirms the electric dipole–quadrupole interaction among the ions. The Judd-Ofelt intensity parameters and other radiative properties were estimated by using PL emission spectra. The photometric characteristics of the prepared samples indicate that the color co-ordinates were tune towards pure red emission with color purity of ∼88%. The results signified that the prepared Y 2 O 3 :Eu 3+ was a potential amber phosphor for solid state and LED’s applications.

Modified sonochemical route was used to prepare Y2O3:Tm3+ (1-11mol%) nanophosphor using Mimosa pudica (M.P.) leaves extract as bio-surfactant. The prepared samples were exhibited high crystalline nature with various morphologies. This was due to sonochemical experimental reaction took place between cavitation bubbles and nearby solution. The average crystallite sizes of the prepared samples were about 15nm to 21nm as obtained from PXRD and TEM analysis. The ultraviolet visible absorption spectra showed prominent bands with an energy gap varied from 5.73eV to 5.84eV. Photoluminescence (PL) emission spectra shows the prominent blue light emission peak at ~456nm attributed to 1D2→3F4 transitions of Tm3+ ions. Judd-Ofelt intensity parameters were estimated by using PL emission spectra. The photometric characteristics of the prepared compounds were very close to the blue color of NTSC standards. So the results were fruitful in making use of Y2O3:Tm3+ nanophosphor as an alternative material for effective blue component in WLED's.

Nano research offered new possibilities in surface-based science includes latent fingerprints and lips print detection on various surfaces. CdSiO 3 :Dy 3+ nanopowders were fabricated via modified sonochemical method. Eccrine prints stained by optimized composition of prepared samples exhibited high sensitivity, low background hindrance on various surfaces compared to traditional fluorescent powders. Surface morphologies were studied with different sonication influential parameters. The estimated average crystallites size and band gap were found to be 22 nm and 5.37 eV respectively. Photometric CIE and CCT values were close to near ultraviolet light with CP of 95% for the prepared compounds confirms their utility in the field of optoelectronics.

In this paper a simple green route was adopted for the synthesis of orange light emitting CaSiO 3 :Pr 3+ (1–11 mol %) phosphors using Mimosa pudica L. extract as a fuel. The final product was well characterized by powder X-ray diffraction (PXRD), Fourier transform infra-red spectroscopy, diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM) and transmission electron microscopy. The concentration of plant extract plays an important role in controlling the morphology as well as the formation of superstructures. The obtained superstructures from SEM studies resembled the naturally existing structures like dates, cactus, coconut shell, etc. The energy band gap estimated using DRS was found to be in the range of 5.23–5.47 eV. The emission peaks at 550, 606, 650 and 733 nm were due to the transitions of 3 P 0 → 3 H 4, 5 , 3 F 2, 3 . The Commission International de I ′Eclairage and colour correlated temperature coordinates were estimated for all the concentrations of Pr 3+ ions and the results indicates that the phosphor may be quite useful in cool light source. The crystalline nature and phase was confirmed by PXRD for the calcined samples at 950 °C for 3 h. This was the lowest formation temperature reported in the literature for Pr 3+ doped CaSiO 3 . FTIR results showed the stretching vibrations of Si-O at 720 cm −1 , asymmetric stretching vibrations of Si-O-Si bonds at 560 cm −1 . The present preparation method was simple, eco-friendly, inexpensive and free from unwanted by-products which can be used for large scale production.

A series of Dy3+-activated Ca2SiO4 phosphors were prepared by low-temperature solution combustion method. The obtained phosphor was well characterized by powder X-ray diffraction, scanning electron microscopy, UV–visible spectroscopy, etc. The average crystallite size was estimated using Scherer's formula and Williamson–Hall plots and was found to be in the range of 40–57 nm. The optical energy band gaps (Eg) for Dy-doped samples were estimated and were found to be in the range of 5.10–5.44 eV. The energy band gap was found to be widened with an increase of Dy3+ ion concentration. Photoluminescence spectra consist of three main groups of peaks in 460–500 nm (blue), 555–610 nm (yellow) and 677 nm (red) regions, respectively, and were assigned to the transitions of 4F9/2 → 6H15/2,13/2,11/2. The chromaticity color coordinates of all the prepared phosphors were found to be in the white region and was quite useful for the white light emitting diodes (WLED's).

Herein, we report hierarchical arrow-like structures of CaZrO3:Dy3+ (1−11 mol %) are prepared by sonochemical route using bio template as a surfactant. High purity and crystallinity of the product was obtained in sonochemical route when compared to conventional methods. Morphological results showed arrow-like structures which are highly reliant on many experimental parameters such as, sonication time, bio-template concentration, sonication power, pH and surfactant to water ratio. The photoluminescence emission spectra consist of sharp peaks at ∼481 nm (blue), 575 nm (yellow) and 665 nm (red), which ascribed to 4F9/2→6H15/2, 4F9/2→6H13/2 and 4F9/2→6H11/2 transitions of Dy3+ ions, respectively. The decrement in the photoluminescence emission intensity after 7 mol % of Dy3+ ion concentration was clearly noticed, which may due to concentration quenching. The photometric properties of the prepared samples showed intense white emission with high color purity. Thermoluminescence glow curves of CaZrO3:Dy3+ (7 mol %) showed broad and intense peak at ∼143 °C at a warming rate of 2 °C s−1. Thermoluminescence profile reveals the linear dependence with dose, least fading and highly reproducible. The optimized powders are employed to image the latent fingerprints with higher resolution on various porous, non-porous and semi-porous surfaces. The aforementioned results clearly indicate that the optimized hierarchical structures are effectively used in radiation dosimetry, display devices and advanced forensic applications.

Ultra-bright luminescent nanomaterials can be controlled by blended with suitable dopant ions offers a significant strategy to combat the counterfeiters and the reveal latent fingerprints. Herein, we report Pr3+ activated LaOF nanophosphors blended with monovalent alkali metal ions (Na+, K+, Li+) prepared via eco-friendly sonochemical route. The X-ray diffraction profiles confirm the tetragonal crystal system. The photoluminescence emission showed characteristic peaks at ~497, 531, 555, 612, 641, 685, 702 and 734 nm, which corresponds to 3P0→3H4, 3P1→3H5, 3P0→3H5, 3P0→3H6, 3P0→3F2, 3P1→3F3, 3P1→3F4 and 3P0→3F4 transitions Pr3+ ions, respectively. A significant luminescent enhancement was achieved in Li+ co-dopant when compared to Na+ and K+. Upon co-doping, color coordinates shifted from orange to pure red region. The latent fingerprint results on various surfaces clearly showed the high resolution images of active or inactive sweat pores with superior sensitivity and selectivity and low background hindrance. A greater possible stochastic process to make unclonable anti-counterfeiting patterns using optimized nanophosphor was designed to reduce counterfeit products. Therefore, we believe that this optimized nanophosphor for visualization of latent fingerprints as well as unclonable anti-counterfeiting tags find widespread use in advanced forensic investigations and product safety applications.

Blue light emitting neodymium (Nd) doped dicalcium (Ca2SiO4) silicate nanostructures were prepared for the first time via ultrasound assisted sonochemical synthesis route using cetyltrimethylammonium bromide (CTAB) surfactant. The obtained final product was well characterized. The powder X-ray diffraction (PXRD) profiles confirmed that product was highly crystalline in nature with monoclinic phase. Influence of various reaction parameters such as, the effect of sonication time, concentration of the surfactant and pH of the precursor solution on the morphology was studied in detail. Diffuse reflectance spectroscopy (DRS) was studied to evaluate the band gap energy of the products and the values were found in the range of 5.78 – 6.17 eV. The particle size was estimated by transmission electron microscope (TEM) and it was found in the range of 20-30 nm. Photoluminescence (PL) properties were studied in detail by recording emission spectra of all the Nd doped dicalcium silicate nanostructures at an excitation...

Mimosa pudica(MP) plant extract was used to prepare Y2O3:Tm3+ (1-11mol %) nanoscale superstructure with nitrate source as precursors. The samples were characterized by advanced characterization techniques. The PXRD peaks indicates crystalline, no impurity peaks were present with body centre cubic structure of Y2O3. Photoluminescence emission spectra shows blue color emission at 358 nm excitation wavelength. The major peak of Tm3+ was at 453 nm and two very weak peaks were observed at ∼ 474 nm attributed to the transitions of 1D2 → 3 F4 and 1G4 → 3H6, res. The calculated color co-ordinates were matches to the NTSC blue color. Correlated color temperature was ∼ 4000 K. So the Y2O3:Tm3+ nanophosphor could be used for blue component in the warm WLED and SSL devices.

Modified sonochemical route was used to prepare Y

In the past two decades, organic conductors have been widely explored for use in different applications. One of the extensively studied organic material for the use in the field of electronic devices is PEDOT:PSS. Organic/inorganic nanocomposite systems have been developed to improve the properties of organic materials. In the present study, we have made an attempt to understand the effect of low energy oxygen ion beam irradiation on the electrical and structural properties of PEDOT:PSS and PEDOT:PSS/TiO2 nanocomposites. The observed reduction in electrical properties in PEDOT:PSS systems may be linked to radiation induced phase change. The nanocomposite systems show better stability to the ion irradiation compared to the pure systems.

For the first time green route method was used to synthesize pure and Mg2+(1-11 mol %) doped Y2O3 nanophosphors by using Mimosa pudica leaves extract as a fuel. The final product was well characterized by powder x-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and photoluminescence (PL).The PXRD result shows the formation of single phase, cubic structure of Y2O3 with crystallite sizes ~25 nm. The SEM results showed porous and agglomerated structures, TEM images showed the crystallite size of the material and was found to be around ~ 25 nm. PL emission spectra show the blue light emission under the excitation wavelength of 315 nm. The emission peaks of Mg2+were observed at 428 nm, 515 nm and 600 nm corresponding to the transitions of 4F9/2 → 6Hi7/2 (violet), 4F9/2 → 6Hi5/2 (blue), 4F9/2 → 6HJ3/2 (yellow) respectively. The estimated CIE chromaticity co-ordinate was very close to the national television standard committee value of blue emission. CCT was found to be ~ 6891 K as a result the present phosphor was potential to be used for warm white light emitting display applications.