1. UNESCO-UNISA Africa Chair in Nanoscience and Nanotechnology College of Graduates Studies, University of South Africa, Pretoria 392, South Africa
2. Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, Somerset West 7129, South Africa
3. Petroleum Engineering, School of Engineering Department, Edith Cowan University, 270 Joondalup Drive, Perth, WA 6027, Australia
4. Institute for Nanotechnology and Water Sustainability (iNanoWS), College of Science, Engineering and Technology, University of South Africa, Private Bag X6, Florida Science Campus, Johannesburg 1709, South Africa
5. Department of Chemical Sciences, University of Johannesburg, Doornfontein, Johannesburg 2028, South Africa