Synthesis of Cu-Doped ZnO/Ag/CuO Heterostructure: The Charge Transfer and Synergetic Effect on Anti-bacterial Activity and Methylene Blue Dye Degradation

Abstract

It is observed that doped semiconductor heterostructures exhibit better properties than the separate constituents from which they are formed. In this work synthesis of porous structures using the bottom-up combustion (BUC) approach and effects of doping and heterojunction on charge transfer and visible light harvesting properties were studied. porous materials was produced using BUC approach as a result of gaseous by-products being removed. The XRD-based optimization showed that 1.00 g of PVA, 50 °C synthesis temperature, and 1 hour calcination time were obtained to be the optima. The XRD spectra analysis also showed the material's crystalline nature. The HR-TEM images and XRD patterns also confirm the formation of Cu-doped ZnO and ZnO/Ag/CuO (c-zac) heterostructures. The c-zac also has better optoelectrical and charge transfer properties than single ZnO. The c-zac heterostructure showed improved photocatalytic potential (k = 0.067 min-1) compared to single ZnO (k = 0.0041 min-1). This photocatalysis potential is associated with improved light absorption and charge transfer properties. The extended visible light absorption is due to the copper doping and surface plasmon resonance properties of silver. Antibacterial efficacy of the bottom-up combustion synthesized (uncalcined and calcined) ZnO and c-zac against bacterial pathogens was also assessed. The c-zac NCs exhibited broad spectrum activities against Streptococcus Pyogenes, with inhibition zone of 17.5 ±0.7mm. Least activity was seen against E-coli with inhibition zone of 6±0.7mm. The ZnO and c-zac showed promising antibacterial action against human bacterial pathogens, making them useful in the medical field. The synthesized materials have great activity on gram positive bacteria than gram negative bacteria. Thus, the c-zac heterostructure has a promising future outlook and scale-up potential as a catalytic and antimicrobial agent.