Cu-doped ZnO/Ag/CuO heterostructure: superior photocatalysis and charge transfer

• Published in: RSC advances 2024-09, Vol.14 (41), p.29763-29773
• Main Authors: Gebretsadik, Abbay, Kefale, Bontu, Sori, Chaluma, Tsegaye, Dereje, Ananda Murthy, H. C, Abebe, Buzuayehu
• Format: Article
• Language: English
• Subjects: Charge transfer; Chemistry; Copper; Copper oxides; Electromagnetic absorption; Electrons; Heterojunctions; Heterostructures; High resolution electron microscopy; Image resolution; Methylene blue; Photocatalysis; Polyvinyl alcohol; Silver; Surface plasmon resonance; Synthesis; X-ray diffraction; Zinc oxide; Zinc oxides
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d4ra05989a

Doped semiconductor heterostructures have superior properties compared to their components. In this study, we observed the synthesis of Cu-doped ZnO/Ag/CuO heterostructure with the presence of charge transfer and visible light-harvesting properties resulting from doping and heterojunction. The porous heterostructures were prepared using the bottom-up combustion (BUC) approach. This method generated porous heterostructures by eliminating gaseous by-products. X-ray diffraction (XRD) optimization revealed that the ideal conditions included 1.00 g of polyvinyl alcohol (PVA), a synthesis temperature of 50 °C, and a 1 hour calcination time. Introducing copper (Cu) into the zinc oxide (ZnO) lattice caused a high-angle shift in the XRD pattern peaks. High-resolution transmission electron microscopy (HRTEM) images and XRD patterns confirmed the formation of Cu-doped ZnO/Ag/CuO (c-zac) heterostructures. Elemental mapping analysis confirmed the even surface distribution of Ag metal. The c-zac heterostructures exhibited superior optoelectrical and charge transfer properties compared to single ZnO. The heterostructures demonstrated improved methylene blue (MB) dye degradation potential ( k = 0.065 min −1 ) compared to single ZnO ( k = 0.0041 min −1 ). This photocatalytic potential is attributed to enhanced light absorption and charge transfer properties. The extended visible light absorption resulted from CuO and Ag's surface plasmon resonance properties. The selected 15c-zac heterostructure also performed well in a reusability photocatalytic test, remaining effective until the 3 rd cycle. Consequently, this heterostructure holds promise for scaling up as a catalyst for environmental remediation. The doped porous heterostructure material was synthesised using the combustion approach. It has better photocatalysis potential than the separate constituents.