Synthesis, characterization and application of ZnO-Ag as a nanophotocatalyst for organic compounds degradation, mechanism and economic study.
The current work deals with ZnO-Ag nanocomposites (in the wide range of x in the Zn1-xO-Agx chemical composition) synthesized using microwave assisted solution combustion method. The structural, morphological and optical properties of the samples were characterized by XRD (X-ray diffraction), FTIR (Fourier transform infrared spectrometry), SEM (scanning electron microscopy technique), EDX (energy dispersive X-ray spectrum), ICP (inductively coupled plasma technique), TEM (transmission electron microscopy), BET (Brunauer-Emmett-Teller method), UV-Vis (ultraviolet-visible spectrophotometer) and photoluminescence spectrophotometer. The photocatalytic activity of the ZnO-Ag was investigated by photo-degradation of Acid Blue 113 (AB 113) under UV illumination in a semi-batch reactor. This experiment showed that ZnO-Ag has much more excellent photocatalytic properties than ZnO synthesized by the same method. The enhanced photocatalytic activity was due to the decrease in recombination of photogenerated electron-holes. The results showed the improvement of ZnO photocatalytic activity and there is an optimum amount of Ag (3.5mol%) that needs to be doped with ZnO. The effect of operating parameters such as pH, catalyst dose and dye concentration were investigated. The reaction byproducts were identified by LC/MS (liquid chromatography/mass spectrometry) analysis and a pathway was proposed as well. Kinetic studies indicated that the decolorization process follows the first order kinetics. Also, the degradation percentage of AB 113 was determined using a total organic carbon (TOC) analyzer. Additionally, cost analysis of the process, the mechanism and the role of Ag were discussed.
Gas Engineering Department, Petroleum University of Technology, Ahwaz, Iran.
S
S
Mohammadzadeh
Department of Environmental Research, Institute for Color Science and Technology, Tehran, Iran. Electronic address: me.olya@gmail.com.
M E
ME
Olya
Department of Nanomaterials and Nanocoatings, Institute for Color Science and Technology, Tehran, Iran.
A M
AM
Arabi
Gas Engineering Department, Petroleum University of Technology, Ahwaz, Iran.
A
A
Shariati
Gas Engineering Department, Petroleum University of Technology, Ahwaz, Iran.
M R
MR
Khosravi Nikou
D001391:Azo Compounds / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry; D052918:Environmental Restoration and Remediation / Q000191:economics / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010782:Photolysis; D012834:Silver / Q000737:chemistry*; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D015034:Zinc Oxide / Q000737:chemistry*
D001391:Azo Compounds; D004396:Coloring Agents; D014874:Water Pollutants, Chemical; D012834:Silver; C015967:Levanol Fast Cyanine 5RN; D015034:Zinc Oxide
Advanced oxidation processes; Degradation; Photocatalyst; Wastewater treatment; ZnO-Ag nanocomposite