Optical properties of undoped and cobalt doped ZnS nanophosphor

• Published in: Materials science in semiconductor processing Vol. 16; no. 2; pp. 467 - 471
• Main Authors: Pathak, C.S., Mandal, M.K., Agarwala, V.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.04.2013; Elsevier
• Subjects: Band gap; Cobalt; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Excitation; Materials science; Materials synthesis; materials processing; Nanomaterials; Nanoparticles; Nanopowders; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Optical absorption; Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Photoluminescence; Photoluminescence properties; Physics; Scanning electron microscopy; Semiconductors; Semiconductors nanoparticles; Zinc sulfides; Semiconductors nanoparticles; Band gap; Photoluminescence properties; Optical absorption; Fluorescence spectroscopy; Chemical method; Doping; Photoluminescence; Fluorescence; XRD; Nanostructures; Nanoparticles; Zinc sulfide; Energy gap; Spectrophotometers; Ambient temperature; Optical properties; Visible radiation; Optical characteristic; Cobalt additions; Scanning electron microscopy; Semiconductor materials; Chemical precipitation; Doped materials; Field emission electron microscopy; Ultraviolet radiation; Phosphors; Morphology; Microstructure; Nanostructured materials; Codoping
• ISSN: 1369-8001; 1873-4081
• DOI: 10.1016/j.mssp.2012.07.009

In the present study, the optical properties of ZnS and cobalt (Co) doped ZnS nanoparticles were investigated at room temperature. ZnS and ZnS:Co nanophosphors were prepared through chemical route, namely the chemical precipitation method and the formation of the nanoparticles were confirmed by X-ray diffraction and field emission scanning electron microscope (FESEM). Band gap energy of the prepared samples is determined by using a UV–vis–NIR spectrophotometer. The photoluminescence property of ZnS and ZnS:Co sample is determined by fluorescence spectroscopy. The sizes of as prepared nanoparticles are found to be in the 8–9nm range. The FESEM morphology shows the formation of nanostructure of ZnS samples. The value of optical band gap has been found to be in the range 4.30–4.03eV. Room temperature photoluminescence (PL) spectrum of the undoped sample exhibits emission in the blue region with multiple peaks under UV excitation. On the other hand, Co2+ doped ZnS samples show enhanced visible light emissions under the same UV excitation wavelength of 310nm.