Sains Malaysiana 51(10)(2022): 3251-3259

http://doi.org/10.17576/jsm-2022-5110-11

 

Hydrogen Production from Water Splitting using TiO2/CoS Composite Photocatalyst

(Penghasilan Hidrogen daripada Pemisahan Air menggunakan Komposit Fotomangkin TiO2/CoS)

 

MUTIA AGUSTINA1, SITI NURUL FALAEIN MORIDON2, AMILIA LINGGAWATI1, KHUZAIMAH ARIFIN2,*, LORNA JEFFERY MINGGU2 & MOHAMMAD B. KASSIM3

 

1Department of Chemistry, Faculty of Mathematic and Natural Science, University of Riau, Kampus Binawidya, Km 12.5, Simpang Baru, Pekanbaru Riau, Indonesia

2Fuel Cell Institute, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

3Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

Diserahkan: 8 Februari 2022/Diterima: 1 Jun 2022

 

Abstract

Photocatalytic water splitting reaction has been considered an ideal method for hydrogen generation. In this study, a composite of TiO2/CoS photocatalyst prepared by hydrothermal synthesis method assisted by ball milling crushing process was used. The TiO2/CoS composites prepared with three variation compositions of 90/10, 80/20, and 70/30 were named M-10, M-20, and M-30, respectively. Field-emission scanning electron microscopy images showed that the morphologies of the composites were porous and uniform of nanospheres. The X-ray diffraction and energy dispersive spectroscopy analyses confirmed the presence of CoS in the composites. Ultraviolet–visible absorption characterization demonstrated the smallest bandgap value of approximately 2.72 eV presented by sample M-30 with the photocurrent density of 0.32 mA cm−2 at 0.9 V vs. Ag/AgCl. The presence of CoS in this study could increase the PC hydrogen generation of TiO2 by nearly 2.5 times. The composites forming a p-n heterojunction between TiO2 and CoS could prevent electron–hole recombination and increase the overall photoactivity of TiO2.

 

Keywords: Composite; hydrogen production; hydrothermal; water splitting

 

Abstrak

Tindak balas pemisahan air secara fotokatalisis telah dianggap sebagai kaedah yang ideal untuk penjanaan hidrogen dengan menggunakan semikonduktor sebagai fotomangkin. Dalam kajian ini, komposit fotomangkin TiO2/CoS yang disediakan melalui kaedah sintesis hidroterma dibantu oleh proses penghancuran penggilingan bebola telah digunakan. Komposit TiO2/CoS yang disediakan dengan tiga komposisi variasi 90/10, 80/20 dan 70/30 masing-masing dinamakan M-10, M-20 dan M-30. Imej mikroskopi elektron pengimbasan pelepasan medan menunjukkan bahawa morfologi komposit adalah berliang dan nanosfera yang seragam. Analisis difraksi sinar-X dan spektroskopi penyebaran tenaga mengesahkan kehadiran CoS dalam komposit. Pencirian penyerapan cahaya ultraungu-nampak menunjukkan nilai celah jalur terkecil kira-kira 2.72 eV yang ditunjukkan oleh sampel M-30 dengan ketumpatan arus foto 0.32 mA cm−2 pada 0.9 V lwn. Ag/AgCl. Kehadiran CoS dalam kajian ini boleh meningkatkan penjanaan hidrogen PC TiO2 sebanyak hampir 2.5 kali ganda. Komposit yang membentuk hetero-simpang p-n antara TiO2 dan CoS boleh mengurangkan penggabungan semula lohong dan elektron serta meningkatkan keseluruhan fotoaktiviti TiO2.

 

Kata kunci: Hidroterma; komposit; pemisahan air; pengeluaran hidrogen

 

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*Pengarang untuk surat-menyurat; email: khuzaim@ukm.edu.my

 

 

 

   

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