Erscheint 4 Ausgaben pro Jahr
ISSN Druckformat: 1093-3611
ISSN Online: 1940-4360
Indexed in
EFFECT OF DIELECTRIC BARRIER DISCHARGE PLASMA TREATMENT ON THE PHOTOLUMINESCENCE AND PHOTOCATALYTIC PROPERTIES OF ZnO POWDER
ABSTRAKT
A dielectric barrier discharge (DBD) plasma was applied to treat commercially available ZnO powders. The performance of untreated and plasma-treated ZnO photocatalysts is discussed in the light of their application for photodegradation of organic pollutants. The photocatalytic activities of plasma-treated and untreated ZnO powders were evaluated by measuring the photodegradation of methyl orange (MO) in aqueous solution exposed to ultraviolet (UV) light. The MO concentration in solution was measured spectrophotometrically (UV-Vis spectrophotometry). The photocatalytic activity, expressed in terms of the methyl orange photodegradation rate, was 2.2 times higher for the plasma-treated sample than for the untreated one. In addition, the kinetic process of photocatalytic degradation of MO was also examined, and the degradation of MO was found to follow a first-order rate law. The results imply that different mechanisms are involved in the decomposition of methyl orange on untreated and plasmatreated catalysts. The samples were also characterized by photoluminescence (PL) spectroscopy. Room temperature PL spectra of ZnO powders displayed two emission bands: excitonic UV emission, and deep level visible emission. Characterization of the ZnO powders by means of photoluminescence indicated that plasma treatment leads to an increase in the UV excitonic emission. The increasing photocatalytic activity after plasma treatment can be attributed to the increased optical quality of ZnO.
-
Ansari Mohsen, Hossein Mahvi Amir, Hossein Salmani Mohammad, Sharifian Mehdi, Fallahzadeh Hossein, Hassan Ehrampoush Mohammad, Dielectric barrier discharge plasma combined with nano catalyst for aqueous amoxicillin removal: Performance modeling, kinetics and optimization study, energy yield, degradation pathway, and toxicity, Separation and Purification Technology, 251, 2020. Crossref