1. Molecular
Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg 2050, South Africa
2. DST-NRF Centre of Excellence in Catalysis (c*change), Rondebosch 7701 South Africa
3. Department
of Chemical Engineering, University of South Africa, Private Bag X6, Florida 1710, South Africa
4. DST-NRF Centre of Excellence in Strong Materials, Johannesburg 2050, South Africa