Enhancement of green luminescence of ZnO powders by annealing with carbon black

Journal Article · Mon Aug 04 04:00:00 EDT 2008 · Materials Research Bulletin

DOI:https://doi.org/10.1016/j.materresbull.2007.09.002· OSTI ID:21144078

Chen, H -J ^[1]

---

1. Department of Materials Engineering, Tatung University, Taipei, Taiwan (China)

This paper reports the characterization of nanocrystalline ZnO powders synthesized by a precipitation method and annealed with carbon black. The X-ray diffraction (XRD) and Fourier Transformed Infrared (FT-IR) results revealed that the synthesized ZnO powder has the wurtzite structure with absorbed CO{sub 3}{sup -} species on the surface of the ZnO particles. Singly ionized oxygen vacancy (V{sub O}{sup +}) and CO{sub 3}{sup -} species were also perceived from electron paramagnetic resonance (EPR) analysis. The intensity of the EPR signals of CO{sub 3}{sup -} species increased as the amount of carbon increased whereas that of V{sub O}{sup +} did not vary significantly. A green emission at 528 nm for the powders annealed with carbon was observed and a good correlation between the intensity of green emission and the intensity of EPR signals of CO{sub 3}{sup -} was obtained Experimental results suggest that the formation of the free carriers has significant effect on the intensity of the green emission. The mechanism responsible for the green emission enhancement based on the relevance of the observations is discussed.

• OSTI ID: 21144078
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 8-9 Vol. 43; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
CARBON BLACK
CERAMICS
CRYSTALS
ELECTRON SPIN RESONANCE
INFRARED SPECTRA
LUMINESCENCE
NANOSTRUCTURES
POWDERS
PRECIPITATION
SYNTHESIS
VACANCIES
X-RAY DIFFRACTION
ZINC OXIDES