Manpreet Kaur; Akshay Kumar; Manoj Sharma
Abstract
Composition regulation of semiconductors can engineer the band gap and thus tune the optical properties. For effective utilization of orange emitting phosphors in color conversion applications blue excitation is necessary. Here in this work, absorption and photoluminescence spectroscopic measurements ...
Read More
Composition regulation of semiconductors can engineer the band gap and thus tune the optical properties. For effective utilization of orange emitting phosphors in color conversion applications blue excitation is necessary. Here in this work, absorption and photoluminescence spectroscopic measurements have been done to study the variation in band gap energy by changing the composition of ZnxCd1-xS nanocrystals. Further, ternary Mn doped ZnxCd1-xS semiconductor nanocrystals have been synthesized via an aqueous route over a wide composition range by adjusting the molar ratio of precursors which leads to tunable bandgap, thus propagate the progressive growth of light absorption and photoluminescence spectra. The variation in tunability of bandgap is due to the change in Cd/Zn ratio. By changing Cd/Zn ratio excitation wavelength shifts from UV to blue colour. Copyright © 2017 VBRI Press.
Poonam R. Kharangarh; Akshay Kumar; Raj K. Sharma; Gurmeet Singh
Abstract
With an objective to develop electrode materials with high specific capacitance and good stability, we prepared Graphene quantum dot-doped with transition metal of HCl by using a facile hydrothermal at different temperatures (~ 800C- 1400C). Samples were characterized by Raman spectroscopy, Powdered ...
Read More
With an objective to develop electrode materials with high specific capacitance and good stability, we prepared Graphene quantum dot-doped with transition metal of HCl by using a facile hydrothermal at different temperatures (~ 800C- 1400C). Samples were characterized by Raman spectroscopy, Powdered X-ray Diffraction (PXRD), U-V Visible Spectroscopy, and Transmission Electron Spectroscopy (TEM). Raman spectroscopy study reveals intensity ratio alters with changes in temperatures. It was found the variation in size with doped GQDs under different temperature conditions from TEM measurements. The observed blue shifts in the energy gap of HCl doped GQDs at higher temperature are attributed to the strong interaction of GQDs with HCl. Electrochemical studies showed a superior strategy for generating transition metals doped GQDs. The higher electrochemical activity has been originated by using cyclic voltammetry of HCl doped GQDs at 1200C and is found to be superior electrodes than all other heated samples. The simplicity of synthesized material suggests electrode to understand the charge storage mechanism for commercial applications. Copyright © 2017 VBRI Press.