1. Department of Chemical, Metallurgical and Materials Engineering Institute of NanoEngineering Research (INER), Tshwane University of Technology Tshwane South Africa
2. Centre for Nanostructures and Advanced Materials, DSI‐CSIR Nanotechnology Innovation Centre Council for Scientific and Industrial Research Pretoria South Africa
3. Department of Chemistry, Faculty of Science Nelson Mandela University Port Elizabeth South Africa
4. Department of Chemical Engineering University of Johannesburg Johannesburg South Africa