Enhancement of structural and optical properties of transparent sodium zinc phosphate glass–ceramics nano composite

Abstract

Transparent sodium phosphate glass–ceramics system according to the composition (55-x) P2O5.(30 + x)ZnO.15Na2O where x = 0, 2.5, 5, 7.5, and 10 was prepared with the melt quenching technique. Different techniques such as XRD and infrared spectroscopy (FTIR) were used to investigate the structure of the studied glass samples and glass–ceramics nano composite. XRD revealed the formation of crystalline phase. The crystalline phase of Na2Zn (P2O7) and Na2ZnP2O7.Zn2P2O7 has been detected which varies according to the ZnO concentration. The density increased whereas molar volume decreased as ZnO content was increased. Optical band gap values, direct and indirect, decreased with increasing ZnO content revealing that bridging oxygen linkage Zn–O-P present in the glass network. The band gaps were found to be ranging between 3.42 and 3.13 eV for indirect transition and ranging between 4.34 and 4.20 eV for direct transitions. It was concluded that the samples have a strong tendency to be crystallized with increasing ZnO content in the sample. This crystallization behavior with increasing the ZnO content affected the structure and optical properties of the prepared samples. In this work, a low cost, wide band gap transparent ceramic with wide range of transparency was prepared and investigated. Such glass–ceramic system is suitable for doping with rare-earth element and/or transition metals for laser and optical devices.

Chromium doped ZnO nanoparticles for energy storage, gas and humidity sensing and spin based electronic devices applications

“…The shoulder band at 612 cm −1 may be assigned to the stretching vibration of Zn-O bonds in octahedral coordinate (Hassan et al 2015a). The increase of Cr +3 doping to ZnO nanoparticles caused the band around 612 cm −1 to shift toward the higher wavenumber 640 cm −1 (in Cr-rich sample), which reveals an increase in the strength of Zn-O bond, that is may attributed to optical phonon confinement by nanostructures, it is highly possible because the nanostructures in our samples are bigger in size than the Bohr exciton radius in ZnO (2.3 nm), this in turn caused the observed increase in its height this is may be due to the stretching vibration of ZnO in the tetrahedral and octahedral coordination respectively may be caused the intensity increase as the Cr content was increased according to the existence of defects states that surrounding to Cr ions (42-43), While, the absorption wide range band 470-570 cm −1 may be due to the stretching vibrational mode of vibrational Zn, and Cr cations (Bodke and Dole 2015;Farag et al 2022).…”

Structural, luminescent and in vitro studies of europium‐doped soda lime phosphate glasses

“…Initially, there is an increase in the bandgap, and then a decrease is observed. The increase in the bandgap is related to the increase in the crosslinking density in the glass matrix [16, 17]. A further decrease in the bandgap is attributed to the alteration in the glass sample due to formation of NBOs.…”

“…The E u values initially decrease and then increase. The increase in E u represents the fact that synthetic glass samples have a higher tendency to convert weak bonds into defects at high concentration of doping [16].…”

XRD, structural, optical, electrical and magnetic properties of ZnO nanoparticles incorporated with Cr as a promising material for different applications

“…The shoulder band at 612 cm − 1 may be assigned to the stretching vibration of Zn-O bonds in octahedral coordinate [26]. The increase of Cr + 3 doping to ZnO nanoparticles caused the band around 612 cm − 1 to shift toward the higher wavenumber 640 cm − 1 (in Crrich sample), which reveals an increase in the strength of Zn-O bond, that is may attributed to optical phonon con nement by nanostructures, it is highly possible because the nanostructures in our samples are bigger in size than the Bohr exciton radius in ZnO (2.3 nm), this in turn caused the observed increase in its height this is may be due to the stretching vibration of ZnO in the tetrahedral and octahedral coordination respectively may be caused the intensity increase as the Cr content was increased according to the existence of defects states that surrounding to Cr ions (39-40), While, the absorption wide range band 470-570 cm − 1 may be due to the stretching vibrational mode of vibrational Zn, and Cr cations [38,41].…”