Fabrication of Nano-Ag Encapsulated on ZnO/Fe[sub.2]V[sub.4]O[sub.13] Hybrid-Heterojunction for Photodecomposition of Methyl Orange

• Published in: Sustainability 2022-12, Vol.14 (23)
• Main Authors: Kaliyamoorthy, Gowthami, Chinnasamy, Surya, Pongiya, Uma Devi, Rajadurai, Vijayalakshmi, Ganesamoorthy, Thirunarayanan, Thambusamy, Stalin, Inbasekaran, Muthuvel
• Format: Article
• Language: English
• Subjects: Dyes and dyeing; Environment; Iron compounds; Management; Methods; Oxygen; Photodegradation; Wastewater; Zinc oxide
• ISSN: 2071-1050; 2071-1050
• DOI: 10.3390/su142316276

Novel silver encapsulated nanocomposite zinc oxide/iron tetra-poly-vanadate (Ag-ZnO/Fe[sub.2] V[sub.4] O[sub.13] ) was synthesized with various wt% of silver (1.0–2.5 wt% of Ag) by cost-effective photo-deposition method under the irradiation of ultraviolet-A (UV-A) light. The nanostructure of the Ag-ZnO/Fe[sub.2] V[sub.4] O[sub.13] was explored by various characterization techniques. The surface functionalities were confirmed by Fourier transform infrared spectra and the crystalline nature of the material was revealed by X-ray diffraction patterns. Furthermore, the surface morphology and the optical properties of the composites were analyzed by scanning electron microscopy, energy dispersive X-ray–elemental color mapping (ECM), high-resolution transmission electron microscopy (HRTEM), ultraviolet–visible diffuse reflectance spectroscopy and photoluminescence. The crystallite size of Ag-ZnO/Fe[sub.2] V[sub.4] O[sub.13] was 28.5 nm which was consistent with HRTEM analysis. The photocatalytic activity was tested against aqueous methyl orange degradation under UV-A light irradiation. In all five runs, the stability of the catalyst was confirmed by reusability measurements and almost 98% of degradation was achieved. A suitable degradation pathway was proposed based on intermediates obtained during the degradation analyzed by gas chromatography–mass spectrometry. Trapping experiments confirmed that the superoxide radical anion (O[sub.2] [sup.•−] ) was considered as the most active species for this degradation process. Complete mineralization was confirmed by the measurements of chemical oxygen demand.