Sains Malaysiana 48(5)(2019): 1129–1135

http://dx.doi.org/10.17576/jsm-2019-4805-22

 

Peningkatan Kecekapan Pemisahan Air Menggunakan g-C3N4 yang Disinar Gama

(Improvement of Water Splitting Efficiency using Gamma Irradiated g-C3N4)

 

NURUL AIDA MOHAMED¹, JAVAD SAFAEI¹, AZNAN FAZLI ISMAIL^2,3, MOHAMAD FIRDAUS MOHAMAD NOH¹, MOHD FAIRUZ SOH¹, MOHD ADIB IBRAHIM¹, NORASIKIN AHMAD LUDIN¹ & MOHD ASRI MAT TERIDI^1*

 

¹Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

²Nuclear Science Program, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

³Center for Frontier Science, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

Received: 3 July 2018/Accepted: 13 March 2019

 

ABSTRAK

Dalam kajian ini, kesan sinar gama ke atas bahan semikonduktor g-C3N4 kGy (0.1 kGy dan 0.5) dibincangkan dan dibandingkan dengan sampel yang tidak disinar untuk melihat perbezaanya. Bahan g-C3N4 disintesis dari urea melalui proses pempolimeran haba pada suhu 520°C. Struktur dan morfologi g-C3N4 dianalisis dengan menggunakan pembelauan Sinar- X (XRD), spektroskopi transformasi Fourier inframerah (FT-IR), mikroskop pengimbas elektron pancaran medan dengan spektroskopi tenaga sinar-X (FESEM-EDX), spektroskopi cahaya nampak - ultraungu (UV-Vis) dan ketumpatan arus (LSV). Sinar gama telah mengubah struktur ikatan g-C3N4 dan mengurangkan sela jalur iaitu daripada 2.80 eV kepada 2.72 eV. Di samping itu, sampel g-C3N4 yang disinar pada 0.1 kGy menghasilkan prestasi lima kali ganda lebih tinggi iaitu daripada 3.59 μAcm-2 kepada 14.2 μAcm-2 pada 1.23 V lawan Ag/AgCl dalam larutan elektrolit 0.5 M Na2SO4 (pH7). Kesimpulannya, keputusan kajian menunjukkan bahan semikonduktor yang dirawat dengan sinar gama berpotensi untuk meningkatkan fotoelektrokimia (PEC) pemisahan air.

 

Kata kunci: g-C3N4, pemisahan air; sela jalur tenaga; sinar gama

 

ABSTRACT

In this study, the effect of gamma radiation on g-C3N4 semiconductor material (0.1 and 0.5 kGy) was discussed and compared to the non-irradiated sample in order to investigate the difference. The g-C3N4 material was synthesised from urea by thermal polymerization at the temperature of 520°C. The structure and morphology of the g-C3N4 were analysed by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope with energy dispersive X-ray spectroscopy (FESEM-EDX), ultraviolet- visible (UV-Vis), profilometer and photocurrent density (LSV). The finding indicates that gamma radiation has changed the bonding structure of the g-C3N4 and reduces the optical band gap energy from 2.80 to 2.72 eV. In addition, the irradiated g-C3N4 sample at 0.1 kGy has five times better performance which increases from 3.59 μAcm-2 to 14.2 μAcm-2 at 1.23 V versus Ag/AgCl in 0.5 M Na2SO4 electrolyte solution (pH7). As a conclusion, this study shows that the treated semiconductor material with gamma-ray potentially to increase the photoelectrochemical efficiency.

 

Keywords: g-C3N4; energy band gap; gamma radiation; water splitting

REFERENCES

Ahmad, S., Khan, M.S., Asokan, K. & Zulfequar, M. 2015. Effect of gamma irradiation on structural and optical properties of thin films of a Cd5Se95-xZnx. Int. J. Thin. Fil. Sci. Tec. 4(2): 103-109.

Al-Hamdani, N.A., Al-Alawy, R.D. & Saba, J.H. 2014. Effect of gamma irradiation on the structural and optical properties of ZnO thin films. IOSR Journal of Computer Engineering (IOSR-JCE) 16(1): 11-16.

Alarcón, J., Ponce, S., Paraguay-Delgado, F. & Rodríguez, J. 2011. Effect of γ-irradiation on the growth of ZnO nanorod films for photocatalytic disinfection of contaminated water. Journal of Colloid and Interface Science 364(1): 49-55.

Arshak, K. & Kerostynska, O. 2003. Gamma irradiation induced changes in the electrical and optical properties of tellurium dioxide thin films. IEEE Sensors Journal 3(6): 717-721.

Chang, Y., Guo, Q., Zhang, J., Chen, L., Long, Y. & Wan, F. 2013. Irradiation effects on nanocrystalline material. Front. Mater. Sci. 7(2): 143-155.

Dong, F., Zhao, Z., Xiong, T., Ni, Z., Zhang, W., Sun, Y. & Ho, W. 2013. In situ construction of G-C3N4 /g-C3N4 metal-free heterojunction for enhanced visible-light photocatalysis. ACS Applied Materials & Interfaces 5(21): 11392-11401.

Fujishima, A. & Honda, K. 1972. Electrochemical photolysis of water at a semiconductor electrode. Nature 238: 37-38.

Huang, S., Jin, Y. & Jia, M. 2013. Electrochimica acta preparation of graphene/Co3O4 Composites by hydrothermal method and their electrochemical properties. Electrochimica Acta 95: 139-145.

Jin, A., Jia, Y., Chen, C., Liu, X., Jiang, J., Chen, X. & Zhang, Z. 2017. Efficient photocatalytic hydrogen evolution on band structure tuned polytriazine/heptazine based carbon nitride heterojunctions with ordered needle-like morphology achieved by an in situ molten salt method. Journal of Physical Chemistry C 121(39): 21497-21509.

Li, Q., He, Y. & Peng, R. 2013. Graphitic carbon nitride (G-C3N4) as a metal-free catalyst for thermal decomposition of ammonium perchlorate. RSC Adv. 5(31): 24507-24512.

Liu, J., Zhang, T., Wang, Z., Dawson, G. & Chen, W. 2011. Simple pyrolysis of urea into graphitic carbon nitride with recyclable adsorption and photocatalytic activity. Journal of Materials Chemistry 21(38): 14398-14401.

Mohd-Nasir, S.N.F., Ebadi, M., Sagu, J.S., Sulaiman, M.Y., Ludin, N.A., Ibrahim, M.A. & Teridi, M.A.M. 2015. Influence of ethylene glycol on efficient photoelectrochemical activity of BiVO4 photoanode via AACVD. Physica Status Solidi (A) Applications and Materials Science 212(12): 2910-2914.

Mohamed, N.A., Safaei, J., Aznan, F.I., Mohamad Noh, M.F., Soh, M.F., Ibrahim, M.A., Ahmad Ludin, N. & Mat Teridi, M.A. 2018. Efficient photoelectrochemical performance of gamma irradiated g-C3N4 and its g-C3N4 @BiVO4 heterojunction for solar water splitting. J. Phys. Chem. C. 123(14): 9013-9026.

Mohil, M. & Kumar, G.A. 2013. Gamma radiation induced effects in TeO2 thin films. Journal of Nano and Electronic Physics 5(2): 5-7.

Peng, D., Wang, H., Yu, K., Chang, Y., Ma, X. & Dong, S. 2016. Photochemical preparation of the ternary composite CdS/Au/g-C3N4 with enhanced visible light photocatalytic performance and its microstructure. RSC Advances 6(81): 77760-77767.

Riyadh, C.H.A., Hussein, H.F. & Al-Fregi, A.A. 2012. The effects of gamma irradiation on the absorption spectra and optical energy gap of selenium dioxide thin films. Science Journal of Physics 2012(2): 1-4.

Safaei, J., Ullah, H., Mohamed, N.A., Noh, M.F.M., Soh, M.F., Tahir, A.A., Ludin, N.A., Ibrahim, M.A., Wan Isahak, W.N.R. & Mat Teridi, M.A. 2018. Enhanced photoelectrochemical performance of Z-scheme g-C3N4/BiVO4 photocatalyst. Applied Catalysis B: Environmental 234: 296-310.

Wang, X., Blechert, S. & Antonietti, M. 2012. Polymeric graphitic carbon nitride for heterogeneous photocatalysis. ACS Catalysis 2: 1596-1606.

Yang, P., Zhao, J., Qiao, W., Li, L. & Zhu, Z. 2015. Ammonia-induced robust photocatalytic hydrogen evolution of graphitic carbon nitride. Nanoscale 7(45): 18887-18890.

Yu, J., Wang, S., Cheng, B., Lin, Z. & Huang, F. 2013. Noble metal-free Ni(OH)2–g-C3N4 composite photocatalyst with enhanced visible-light photocatalytic H2 production activity. Catalysis Science & Technology 3(7): 1782-1789.

Zhang, G., Zhang, J., Zhang, M. & Wang, X. 2012. Polycondensation of thiourea into carbon nitride semiconductors as visible light photocatalysts. Journal of Materials Chemistry 22(16): 8083-8091.

Zhang, J., Chen, X., Takanabe, K., Maeda, K., Domen, K., Epping, J.D., Fu, X., Antonieta, M. & Wang, X. 2010. Synthesis of a carbon nitride structure for visible-light catalysis by copolymerization. Angewandte Chemie-International Edition 49(2): 441-444.

Zhang, L., Jing, D., She, X., Liu, H., Yang, D., Lu, Y., Li, J., Zheng, Z. & Guo, L. 2014. Heterojunctions in G-C3N4/ TiO2 (B) nanofibres with exposed (001) plane and enhanced visible-light photoactivity. J. Mater. Chem. A 2(7): 2071- 2078.

Zhong, D.K.N. 2012. Solar water oxidation by composite cobalt-based catalyst/oxide semiconductor photoanode. Thesis Dr. Fal. University Washington (tidak diterbitkan).

 

*Corresponding author; email: asri@ukm.edu.my