Exfoliated graphite/Selenium-Zinc Oxide Nanocomposites for Photodegradation of Organic Dye in Water and Its Antibacterial Activity Against Aater Borne Pathogens

Document Type : Original Research Paper


1 Department of Chemistry, Federal University of Agriculture Abeokuta, Ogun State, Nigeria

2 Department of Applied Chemistry, University of Johannesburg, Doornfontein 2028, South Africa

3 Biotechnology Centre, Federal University of Agriculture Abeokuta, Ogun State, Nigeria

4 Centre for Nanomaterials Science Research, University of Johannesburg, Doornfontein 2028, South Africa


We report the synthesis and application of a novel Exfoliated graphite/Selenium-Zinc oxide (EG/Se-ZnO) nanocomposite for photodegradation of methylene blue dye and its antibacterial activity. The composite was characterized using XRD, FTIR, SEM and TEM. Applicability of EG/ Se-ZnO nanocomposite as photocatalyst was investigated by the photocatalytic degradation of methylene blue as a model for organic pollutant. The XRD has its highest peak at 101 which indicated that ion diffusion was free from solvent viscosity (peak at 002). FTIR spectra confirmed the formation of EG/Se-ZnO nanocomposite as band at 882 cm-1 and 612 cm-1, 727 cm-1, 1373 cm-1 were associated with vibrational frequency of ZnO lattice and Selenium respectively. The SEM revealed cloudy large particles of the synthesized EG/Se-ZnO composite. TEM image revealed mini-rodlike nanoparticles. 99.5% degradation of methylene blue dye was achieved within 90 minutes of irradiation. The reactions followed first order kinetics with the rate constant of 5.79x10 -2 min-1 and R2 value of 0.9. The enhanced photocatalytic activity of EG/Se-ZnO was ascribed to the capability of graphitic layers to accept and transport electrons from the excited ZnO promoting charge separation. The antibacterial activity was also evaluated for the ZnO (bulk) and EG/Se-ZnO nanocomposite against the control (ciprofloxacin) and zone of inhibition observed was on E. coli and E.cloacae respectively depicted that EG/Se-ZnO was more effective on E. coli relatively to bulk ZnO. Thus, EG/Se-ZnO nanocomposite can be used for photocatalytic organic pollutant degradation.


1. P. Aida, V. F. Rosa Blamea, A. Thomas and C. Salvador. J. Ethnopharmacol. Short Comm. 16 (2001) 93-98.
2. A. A. Abdullah. Journal of Biomaterials and Nanobiotechnology. 8 (2017) 66-82.
3. B. Abebe, P.Y. Om and D. Tania. Environ Sci Pollut Res 6 (2016), 7750-6
4. N.J. Bell, Y.H. Ng, A. Du, H. Coster, S.C. Smith and R. Amal. J. Phys. Chem. C, 115 (2011) 6004–6009.
5. L.C. Clark, G. F. Combs, B. W. Turnbull, E. H. Slate, D. K. Chalker, J. Chow, J. R. Taylo. J. Am Medical Ass, 276 (1996) 1957–1963.
6. N. Helin, W. Qinmin, L. Hongxia, C. Min, M. Changjie, S. Jiming, Z. Shengyi, G. Yuanhao and C. Changle. Materials 7 (2014) 4034-4044.
7. P. V. Lakshmi and R. Vijayaraghavan. Scientific Reports 6 (2016) 38606.
8. S. D Lambert, N. J. D. Graham, C. J. Sollars and D. D. Fowler Water Sci. Technol.36 (2-3) (1997) 173.
9. J.T. Li, M. Li, J. H. Li and H.W. Sun. Handbook on Applications of Ultrasound: Sonochemistry for
Sustainability.Ultrason.Sonochem.(Vol. 14) (2007).
10. O. A. Mohd, M. K. Mohammad, A. A. Sajid, H. C. Moo. Journal of Saudi Chemical Society 19 (2015) 494–50.
11. R. P. Manohar and V. S. Shrivastava. Chemica Sinica 5 (2014) 8-17.
12. National Committee for Clinical Laboratory Standards (NCCLS), (1990) .Man.Clin.Microbiol., 5th Ed.
13. A. T. Phong, and J. W. Thomas.6 (2011) 1553–1558.
14. K.B. Purna, B. Priyakshree, D. Gitashree, K. K. Chaitanya, K. Indrapal, V.S. Manjusha, P. Pallabi, S. Dulen and R. D. Manash R. D. RSC Adv. 6 (2016) 11049
15. M. Sangareswari and M. M. Sundaram. IRJET 2 (2015) 526-537.
16. M. Savoskin, A. Yaroshenko, N. Lazareva, V. Mochalin, and R. Mysyk. J.Phys. Chem. Solids, 67 (2006) 1205–1207.
17. N. Thabile, T. K. Alex, A.O. Arotiba, S. Srinivasan, W. K. Rui and B.M. Bhekie. Applied Surface Science 300 (2014) 159–164.
18. H. Wang and C. S. Xie, J. Phys. Chem. Solids (Nanomaterial) 69 (2008).