Sains Malaysiana 45(8)(2016): 1201–1206

Synthesis of Zinc Selenide/Graphene Oxide Composite via Direct and Indirect Hydrothermal Method

(Sintesis Komposit Zink Selenida/Grafin Oksida melalui Kaedah Hidroterma Langsung dan tidak Langsung)

LEE HAN KEE¹, JOSEPHINE LIEW YING CHYI¹*, ZAINAL ABIDIN TALIB¹, MOHAMMAD SHUHAZLLY MAMAT¹,  JANET LIM HONG NGEE², FAKHRURRAZI ASHARI¹, LEONG YONG JIAN¹, CHANG FU DEE³ & BURHANUDDIN YEOP MAJLIS³

¹Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

²Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

³Institute Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan, Malaysia

Received: 20 April 2015/Accepted: 20 November 2015

ABSTRACT

Zinc selenide/graphene oxide (ZnSe/GO) composite is synthesized using hydrothermal method. Two different methods such as direct and indirect route have been investigated to form the ZnSe/GO composite. In this research, the graphene oxide used was in sheet and liquid form. The synthesized composite was then characterized using X-ray diffraction (XRD) for phase identification, field emission scanning electron microscopy (FESEM) for morphology analysis and ultraviolet-visible spectroscopy (UV-Vis) for optical properties. ZnSe/GO composite showed absorption peak ranging from 460 to 480 nm with the optical band gap obtained through Tauc equation. The optical band gap of the ZnSe/GO composite has been tuned down to a smaller value as compared to the bulk ZnSe compound. The optical band gap has been reduced to around 2.53 eV when liquid graphene oxide was used while around 2.23 to 2.32 eV when graphene oxide sheet was used. The purity of ZnSe/GO composite synthesis via indirect hydrothermal method is higher than those synthesized via direct hydrothermal method. The type of graphene oxide will affect the morphology of the composite where the ZnSe compound was either wrapped by tiny thorn-like substance or graphene oxide layer.

Keywords: Band gap tuning; morphology; UV-vis spectroscopy; x-ray diffraction

ABSTRAK

Komposit zink selenida/grafin oksida (ZnSe/GO) telah dihasilkan menggunakan kaedah hidroterma. Dua kaedah berlainan iaitu secara langsung dan tidak langsung telah dikaji untuk menghasilkan komposit ZnSe/GO. Dalam kajian ini, grafin oksida yang digunakan adalah dalam bentuk lembaran dan cecair. Komposit yang dihasilkan ini kemudian dicirikan dengan menggunakan instrumen pembelauan sinar-X (XRD) untuk mengenal pasti fasa sampel, mikroskopi medan pancaran pengimbasan elektron (FESEM) untuk analisis morfologi dan spektroskopi ultraungu/boleh nampak (UV-Vis) untuk mengenal pasti sifat optiknya. Komposit ZnSe/GO menunjukkan puncak penyerapan dalam lingkungan 460 hingga 480 nm dengan jurang jalur optik diperoleh melalui persamaan Tauc. Jurang jalur optik ZnSe/GO komposit telah dikurangkan ke nilai yang lebih kecil berbanding dengan kompaun ZnSe. Jurang jalur optik telah dikurangkan ke 2.53 eV apabila cecair grafin oksida digunakan manakala antara 2.23 hingga 2.32 eV apabila lembaran grafin oksida digunakan. Ketulenan sebatian ZnSe/GO yang dihasilkan melalui kaedah hidroterma secara tidak langsung adalah lebih tinggi berbanding dengan komposit yang dihasilkan melalui kaedah hidroterma secara langsung. Jenis grafin oksida akan memberi kesan terhadap morfologi komposit dengan sebatian ZnSe sama ada dibalut oleh bahan duri kecil atau lapisan grafin oksida.

Kata kunci: Morfologi; pembelauan sinar-X; penalaan jurang jalur; spektroskopi UV-Vis

REFERENCES

Askeland, D., Fulay, P. & Wright, W. 2011. The Science and Engineering of Materials. 6th ed. Stamford: CT.

Bhaskar, S., Dobal, P.S., Rai, B.K., Katiyar, R.S., Bist, H.D., Ndap, J.O. & Burger, A. 1999. Photoluminiscence study of deep levels in Cr-doped ZnSe. Journal of Applied Physics 85(1): 439-443.

Han, J., Xue, S., Zhou, W., Wu, S., Xie, P. & Zou, R. 2014. Cactus-like and honeycomb-like Zinc Selenide microspheres on graphene oxide sheets with excellent optical properties. Journal of Colloid and Interface Science 430: 116-120.

Kumaresan, R., Ichimura, M. & Arai, E. 2002. Chemial deposition of ZnSe polycrystalline thin films and their characterization. Thin Solid Films 414: 25-30.

Li, X.S., Zhu, Y.W., Cai, W.W., Borysiak, M., Han, B.Y., Chen, D., Piner, R.D., Colombo, L.G. & Ruoff, R.S. 2009. Transfer of large-area graphene films for high-performance transparent conductive electrodes. Nano Letters 9(12): 4359-4363.

Liu, C., Ji, Y. & Tan, T. 2013. One-pot hydrothermal synthesis of water-dispersible ZnS quantum dots modified with mercaptoacetic acid. Journal of Alloys and Compounds 570: 23-27.

Lokhande, C.D., Patil, P.S., Tributsh, H. & Ennaoui, A. 1998. Formation of II-VI nanocrystals in a novel phosphate glass. Journal of Crystal Growth 184-185: 365-369.

Muller, M., Brauninger, M. & Trauzettel, B. 2009. Temperature dependence of the conductivity of ballistic graphene. Physical Review Letters 103: 196801-196805.

Patel, J.D., Mighri, F. & Ajji, A. 2014. A facile route towards preparation of ZnSe nanocrystals. Materials Letters 131: 366-369.

Segovia, M., Lemus, K., Moreno, M., Santa Ana, M.A., Gonzalez, G., Ballesteros, B., Sotomayor, C. & Benaventa, E. 2011. Zinc oxide/carboxylic acid lamellar structures. Materials Research Bulletin 46(11): 2191-2195.

Syuhada, N.I., Huang, N.M., Vijay Kumar, S., Lim, H.N., Rahman, S.A., Thien, G.S.H., Ibrahim, N.A., Ahmad, M. & Moradihamedani, P. 2014. Enhanced mechanical properties of chitosan/EDTA-GO nanocomposites thin films. Sains Malaysiana 43(6): 851-859.

Wu, C.X., Li, F.S., Zhang, Y.G. & Guo, T.L. 2012. Improving the field emission of graphene by depositing zinc oxide nanorods on its surface. Carbon 50: 3622-3626.

Zhu, J., Koltypin, Y. & Gedankem, A. 2000. General sonochemical method for the preparation of nanophasic selenides: Synthesis of ZnSe nanoparticles. Chemistry of Materials 12(1): 73-78.

*Corresponding author; email: josephine@upm.edu.my