Abstract
Co2+-doped MgCr2O4 nanocrystals were prepared by a microwave method. Polyvinyl alcohol (PVA), as well as Mg and Cr nitrates, with a molar ratio of metal ion to PVA monomer unit of 1:3, was irradiated with 2.45 GHz microwaves at microwave powers ranging from 400 to 900 W. These were used as precursors for Co2+-doped MgCr2O4 spinels. The Co2+-doped MgCr2O4 nanocrystals were produced by calcining the precursors at temperatures above 500°C. They were then characterized by X-ray diffraction (XRD), the results of which suggest that MgCr2O4 nanocrystals with good spinel structures can be prepared via the microwave method. Infrared (IR) spectra showed that PVA was decomposed. The observed excitation and emission spectra of nanocrystalline powders in the visible regions were characteristic of tetrahedral Co2+ ions, indicating that Co2+ ions entered the MgCr2O4 crystal by replacing tetrahedral Mg2+ ions. The bands at 677.6 nm are assigned to spin-allowed 4T1(4P) →4A2(4F) transitions.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
