1. Department of Chemical Sciences (formerly known as Applied Chemistry), University of Johannesburg, P.O Box 17011, Doornfontein, Johannesburg 2028, South Africa
2. Department of Chemistry, University of Limpopo, Sovenga, Polokwane 0727, South Africa
3. Energy, Water, Environmental and Food Sustainable Technologies (EWEF-SusTech), Johannesburg 1709, South Africa