ZnO Nanostructures Doped with Various Chloride Ion Concentrations for Efficient Photocatalytic Degradation of Methylene Blue in Alkaline and Acidic Media
Razan A. Alshgari,
Zaheer Ahmed Ujjan,
Aqeel Ahmed Shah,
Muhammad Ali Bhatti,
Aneela Tahira,
Nek Muhammad Shaikh,
Susheel Kumar,
Mazhar Hussain Ibupoto,
Amal Elhawary,
Ayman Nafady,
Brigitte Vigolo,
Zaffar Hussain Ibhupoto
Affiliations
Razan A. Alshgari
Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
Zaheer Ahmed Ujjan
Institute of Physics, University of Sindh Jamshoro, Jamshoro 76080, Pakistan
Aqeel Ahmed Shah
Department of Metallurgy, NED University of Engineering and Technology Karachi, Karachi 75270, Pakistan
Muhammad Ali Bhatti
Institute of Environmental Sciences, University of Sindh Jamshoro, Jamshoro 76080, Pakistan
Aneela Tahira
Institute of Chemistry, Shah Abdul Latif University Khairpur Mirs, Khairpur Mirs 66020, Pakistan
Nek Muhammad Shaikh
Institute of Physics, University of Sindh Jamshoro, Jamshoro 76080, Pakistan
Susheel Kumar
Institute of Physics, University of Sindh Jamshoro, Jamshoro 76080, Pakistan
Mazhar Hussain Ibupoto
Department of Zoology, Shah Abdul Latif University Khairpur Mirs, Khairpur Mirs 66020, Pakistan
Amal Elhawary
Department of Chemistry and physics, Faculty of Education, Alexandria University, Alexandria 21500, Egypt
Ayman Nafady
Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
Brigitte Vigolo
College of Natural Resources and Sciences, Jean Lamour Institute, Université de Lorraine, F-54000 Nancy, France
Zaffar Hussain Ibhupoto
Institute of Chemistry, University of Sindh Jamshoro, Jamshoro 76080, Pakistan
In this study, chloride (Cl−) ions were successfully doped into ZnO nanostructures by the solvothermal method. The effect of various Cl− concentrations on the photocatalytic activity of ZnO towards the photodegradation of methylene blue (MB) under the illumination of ultraviolet light was studied. The as-prepared Cl−-doped ZnO nanostructures were analyzed in terms of morphology, structure, composition and optical properties. XRD data revealed an average crystallite size of 23 nm, and the XRD patterns were assigned to the wurtzite structure of ZnO even after doping with Cl−. Importantly, the optical band gap of various Cl ion-doped ZnO nanostructures was successively reduced from 3.42 to 3.16 eV. The photodegradation efficiency of various Cl− ion-doped ZnO nanostructures was studied for MB in aqueous solution, and the relative performance of each Cl ion-doped ZnO sample was as follows: 20% Cl−-doped ZnO > 15% Cl−-doped ZnO > 10% Cl−-doped ZnO > 5% Cl−-doped ZnO > pristine ZnO. Furthermore, the correlation of the pH of the MB solution and each Cl ion dopant concentration was also investigated. The combined results of varying dopant levels and the effect of the pH of the MB solution on the photodegradation process verified the crucial role of Cl− ions in activating the degradation kinetics of MB. Therefore, these newly developed photocatalysts could be considered as alternative materials for practical applications such as wastewater treatment.
