Facile synthesis of CuO/CdS heterostructure photocatalyst for the effective degradation of dye under visible light

Sk Safdar Hossain; Mostafa Tarek; Thurga Devi Munusamy; Kaykobad Md Rezaul Karim; Selvaraj Mohana Roopan; Shaheen M Sarkar; Chin Kui Cheng; Md Maksudur Rahman Khan

doi:10.1016/j.envres.2020.109803

Facile synthesis of CuO/CdS heterostructure photocatalyst for the effective degradation of dye under visible light

Environ Res. 2020 Sep:188:109803. doi: 10.1016/j.envres.2020.109803. Epub 2020 Jun 16.

Authors

Sk Safdar Hossain¹, Mostafa Tarek², Thurga Devi Munusamy², Kaykobad Md Rezaul Karim², Selvaraj Mohana Roopan³, Shaheen M Sarkar⁴, Chin Kui Cheng², Md Maksudur Rahman Khan⁵

Affiliations

¹ Department of Chemical Engineering, College of Engineering, King Faisal University, Al-Ahsa 31982, Kingdom of Saudi Arabia.
² Department of Chemical Engineering, College of Engineering, Universiti Malaysia Pahang, 26300, Gambang, Pahang, Malaysia.
³ Chemistry of Heterocycles & Natural Product Research Laboratory, Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore, Tamilnadu, 632 014, India.
⁴ Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, V94, Ireland.
⁵ Department of Chemical Engineering, College of Engineering, Universiti Malaysia Pahang, 26300, Gambang, Pahang, Malaysia. Electronic address: mrkhancep@yahoo.com.

PMID: 32590149
DOI: 10.1016/j.envres.2020.109803

Abstract

In this work, the photocatalytic property of p-type CuO was tailored by creating a heterojunction with n-type CdS. The CuO/CdS nanocomposite photocatalyst was synthesized by the ultrasound-assisted-wet-impregnation method and the physicochemical and optical properties of the catalysts were evaluated by using N₂ physisorption, X-Ray Diffraction (XRD),X-Ray Photoelectron Spectroscopy (XPS), Raman spectroscopy, Transmission electron microscopy (TEM), Energy dispersive X-Ray (EDX) mapping, Field Emission Scanning Electron Microscope (FE-SEM), UV-Vis and photoluminescence spectroscopy experiments. Detailed characterization revealed the formation of a nanocomposite with a remarkable improvement in the charge carrier (electron/hole) separation. The photocatalytic degradation efficiencies of CuO and CuO/CdS were investigated for different dyes, for instance, rhodamine B (RhB), methylene blue (MLB), methyl blue (MB) and methyl orange (MO) under visible light irradiation. The obtained dye degradation efficiencies were ~93%, ~75%, ~83% and ~80%, respectively. The quantum yield for RhB degradation under visible light was 6.5 × 10^-5. Reusability tests revealed that the CuO/CdS photocatalyst was recyclable up to four times. The possible mechanisms for the photocatalytic dye degradation over CuO/CdS nanocomposite were elucidated by utilizing various scavengers. Through these studies, it can be confirmed that the conduction band edges of CuO and CdS play a significant role in producing O₂^-. The produced O₂^- degraded the dye molecules in the bulk solution whereas the valence band position of CuO acted as the water oxidation site. In conclusion, the incorporation of CuO with CdS was demonstrated to be a viable strategy for the efficient photocatalytic degradation of dyes in aqueous solutions.

Keywords: CuO/CdS; Heterostructure photocatalyst; Photodegradation; Rhodamine B; Visible light.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Catalysis
Coloring Agents
Copper*
Light*

Substances

Coloring Agents
Copper
cupric oxide