Loading...

Shed light on submerged DC arc discharge synthesis of low band gap gray Zn/ZnO nanoparticles: Formation and gradual oxidation mechanism

Ziashahabi, A ; Sharif University of Technology | 2018

1614 Viewed
  1. Type of Document: Article
  2. DOI: 10.1016/j.apt.2018.02.017
  3. Publisher: Elsevier B.V , 2018
  4. Abstract:
  5. Synthesis of colloidal metal oxides with controllable size and morphology is burgeoning field of research in nanoscience. Low band gap gray Zn/ZnO colloidal nanoparticles were fabricated by plasma-liquid interaction of DC arc discharge in water. Scanning electron microscopy, X-ray diffraction and UV–vis spectroscopy were employed for morphology, crystal structure and optical characterizations respectively. Optical emission spectroscopy was used to investigate the plasma properties during the synthesis and formation mechanism of nanoparticles. Nanoparticles with different size and shape were fabricated only by adjusting discharge current during synthesis without introducing any chemical agent. Electric discharge current was set to 20, 50, 100 and 150 A during synthesis. Estimated values of plasma excitation energies were 2.41, 2.66, 2.86 and 3.04 eV and diameter size of nanoparticles were 63, 42, 37 and 29 nm for these applied currents respectively. Synthesized nanoparticles were dark gray as prepared and became more transparent gradually getting white color finally. XRD and UV–vis results revealed that the oxidation process was time dependent. The colloidal nanoparticles composed of two metal and metal-oxide phase and white crystalline ZnO was achieved after complete oxidation process. These results provided a flexible and versatile method to synthesize metal oxide nanoparticles with controlled composition. © 2018 The Society of Powder Technology Japan
  6. Keywords:
  7. Arc discharge ; Optical emission spectroscopy ; Oxidation mechanism ; Zn/ZnO nanoparticles ; Colloids ; Crystal structure ; Electric discharges ; Energy gap ; II-VI semiconductors ; Light emission ; Metal nanoparticles ; Metallic compounds ; Metals ; Nanoparticles ; Oxidation ; Oxidation resistance ; Scanning electron microscopy ; Ultraviolet visible spectroscopy ; X ray diffraction ; Zinc ; ZnO nanoparticles ; Arc discharge ; Colloidal nanoparticles ; Complete oxidation ; Formation mechanism ; Metal oxide nanoparticles ; Optical characterization ; Oxidation mechanisms ; UV-vis spectroscopy ; Synthesis (chemical)
  8. Source: Advanced Powder Technology ; Volume 29, Issue 5 , 2018 , Pages 1246-1254 ; 09218831 (ISSN)
  9. URL: https://www.sciencedirect.com/science/article/pii/S0921883118300591