Abstract

Solid-state synthesis of ZnS nanoparticle via mechanical milling process

Author(s): M.S.Al-Kotb, H.Selim, H.H.Amer, M.M.Khalil, M.F.Kotkata

Zinc sulfide (ZnS) quantum dots (QDs) were prepared via a novel solid– state reaction by milling appropriate amounts of zinc acetate and thioacetamide at room temperature. The structural nature and optical properties of the as-synthesized nanoparticles were characterized by using:X-ray diffraction (XRD), energy dispersive X-rays analysis (EDX), transmission electronmicroscopy (TEM), Fourier transforminfrared (FTIR) and thermo gravimetric analysis (TGA).The particle size of the produced ZnS lies in the range of 2.95±0.13–4.23±0.039 nm, depending on the milling period (1: 4 hrs), and in comparison to the Bohr radius of ZnS (2.5 nm).The TGA revealed stability of all products up to ~500oC, after which ZnS were found to react with O2 to produce ZnO as confirmed by XRD and FT-IR. The optical propertieswere studied by analyzing the recorded UV-Vis and photoluminescence (PL) spectra. The optical band gap of the assynthesized ZnS QDs lies in the range of 4.24–4.60 eV depending on the milling period. PL excitation peak shows a blue shift for ZnS-QDs obtained by milling. This blue shift could be attributed to a secondary effect of photo- corrosion process, which is in other words attributed as reduction in diameter of the ZnS QDs.


Share this       
izmir escort izmir escort bursa escort antalya escort izmir escort porno porno izle türk porno eskişehir escort bartın escort burdur escort izmir escort bursa escort porno indir izle istanbul escort istanbul escort bayan escort izmir