1. Department of Applied Chemistry, University of Johannesburg, Johannesburg, South Africa
2. Department of Metallurgy – Faculty of Engineering and the Built Environment, Mineral Processing and Technology Research Center, University of Johannesburg, Johannesburg, South Africa
3. Department of Chemistry, University of Johannesburg, Johannesburg, South Africa
4. Centre for Nanomaterials Science Research, Faculty of Science, University of Johannesburg, Johannesburg, South Africa