The present work is involved in the synthesize, characterization and evaluating the role of CuO o... more The present work is involved in the synthesize, characterization and evaluating the role of CuO on physical, structural and optical properties of 45P 2 O 5-(55-x)Na 2 O-xCuO (x = 0, 1.0, 3.0 and 5.0 mol%) compositions. The as-synthesized samples are characterized by various experimental techniques such as XRD, FTIR, Raman and UV visible spectroscopy to study their suitability for laser and non-linear optical applications. The density of glasses increases whereas molar volume decreases from with the doping of CuO in place of Na 2 O. The amorphous nature of the prepared samples is confirmed by X-ray pattern. FTIR and Raman spectra confirm the presence of metaphosphate (Q 2) and orthophosphate (Q 0) structural units in the prepared glass samples which confirms that the glass network become more polymerised with the addition of CuO in place of Na 2 O. The optical band gap increases from 1.94 to 4.11 eV whereas refractive index decreases from 2.76 to 2.14 with increasing doping of CuO. The molar refraction decreases while metallization criteria increase with CuO doping. This glass material demonstrates promising potential for applications in non-linear optics.
For 7 Li-enriched La 2/3-x 7 Li 3x TiO 3 samples quenched into liquid nitrogen and cooled in the ... more For 7 Li-enriched La 2/3-x 7 Li 3x TiO 3 samples quenched into liquid nitrogen and cooled in the furnace, impedance measurements and time-of-flight neutron powder diffraction (TOF-NPD) experiments were carried out in order to study the effect of the quenched-into-liquid-nitrogen treatment for the ionic conduction and the structural properties. It was found that the quenched-into-liquid-nitrogen treatment enhances the lithium ionic conductivity in the 7 Li-content range between 3x ~ 0.25 and 0.45. Furthermore, the local structure within 6 Å did not change, according to the atomic pair density function (PDF) analysis.
Glass and glass ceramic samples with composition 55SiO2–30B2O3–(x)Li2O–(15 x)Y2O3, where x =0,5... more Glass and glass ceramic samples with composition 55SiO2–30B2O3–(x)Li2O–(15 x)Y2O3, where x =0,5,10, 15 are prepared by conventional melt-quench technique. The structural, physical, thermal, optical, mechanical and conducting properties of these glasses are studied using X-ray diffraction (XRD), Differential Thermal Analyzer (DTA), Fourier Transform Infrared spectroscopy (FTIR), UV–visible spectroscopy and Impedance spectroscopy. Theoretical elastic moduli are calculated for the better understanding of the glass network strength. All samples, except with x = 0 glass, are amorphous in nature. Two broad halos are observed in x = 5 and x = 10 glasses, indicating phase separation in these glasses. Optical band gap of the samples decreases with increasing Y2O3 content. The lowest band gap is observed 3.60 eV for x = 15 glass. Urbach energy increased with an increase in Y2O3 concentration. Y2O3 played different roles at different concentrations and enhanced the phase separation tendency in glass. The typical conductivity was observed 106 S/cm at 620 C for x = 10 glass.
The present work is involved in the synthesize, characterization and evaluating the role of CuO o... more The present work is involved in the synthesize, characterization and evaluating the role of CuO on physical, structural and optical properties of 45P 2 O 5-(55-x)Na 2 O-xCuO (x = 0, 1.0, 3.0 and 5.0 mol%) compositions. The as-synthesized samples are characterized by various experimental techniques such as XRD, FTIR, Raman and UV visible spectroscopy to study their suitability for laser and non-linear optical applications. The density of glasses increases whereas molar volume decreases from with the doping of CuO in place of Na 2 O. The amorphous nature of the prepared samples is confirmed by X-ray pattern. FTIR and Raman spectra confirm the presence of metaphosphate (Q 2) and orthophosphate (Q 0) structural units in the prepared glass samples which confirms that the glass network become more polymerised with the addition of CuO in place of Na 2 O. The optical band gap increases from 1.94 to 4.11 eV whereas refractive index decreases from 2.76 to 2.14 with increasing doping of CuO. The molar refraction decreases while metallization criteria increase with CuO doping. This glass material demonstrates promising potential for applications in non-linear optics.
For 7 Li-enriched La 2/3-x 7 Li 3x TiO 3 samples quenched into liquid nitrogen and cooled in the ... more For 7 Li-enriched La 2/3-x 7 Li 3x TiO 3 samples quenched into liquid nitrogen and cooled in the furnace, impedance measurements and time-of-flight neutron powder diffraction (TOF-NPD) experiments were carried out in order to study the effect of the quenched-into-liquid-nitrogen treatment for the ionic conduction and the structural properties. It was found that the quenched-into-liquid-nitrogen treatment enhances the lithium ionic conductivity in the 7 Li-content range between 3x ~ 0.25 and 0.45. Furthermore, the local structure within 6 Å did not change, according to the atomic pair density function (PDF) analysis.
Glass and glass ceramic samples with composition 55SiO2–30B2O3–(x)Li2O–(15 x)Y2O3, where x =0,5... more Glass and glass ceramic samples with composition 55SiO2–30B2O3–(x)Li2O–(15 x)Y2O3, where x =0,5,10, 15 are prepared by conventional melt-quench technique. The structural, physical, thermal, optical, mechanical and conducting properties of these glasses are studied using X-ray diffraction (XRD), Differential Thermal Analyzer (DTA), Fourier Transform Infrared spectroscopy (FTIR), UV–visible spectroscopy and Impedance spectroscopy. Theoretical elastic moduli are calculated for the better understanding of the glass network strength. All samples, except with x = 0 glass, are amorphous in nature. Two broad halos are observed in x = 5 and x = 10 glasses, indicating phase separation in these glasses. Optical band gap of the samples decreases with increasing Y2O3 content. The lowest band gap is observed 3.60 eV for x = 15 glass. Urbach energy increased with an increase in Y2O3 concentration. Y2O3 played different roles at different concentrations and enhanced the phase separation tendency in glass. The typical conductivity was observed 106 S/cm at 620 C for x = 10 glass.
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