1. Department of Chemistry; Kwame Nkrumah University of Science and Technology, PMB; Kumasi Ghana
2. The School of Chemistry; The University of Manchester, Oxford Road; Manchester M13 9PL United Kingdom.
3. The School of Materials; The University of Manchester, Oxford Road; Manchester M13 9PL United Kingdom.
4. Department of Chemistry; University of Zululand, Private Bag X1001; KwaDlangezwa 3886 South Africa.