Dalton Transactions PAPER Cite this: Dalton Trans., 2020, 49, 8314 Received 16th April 2020, Accepted 22nd May 2020 DOI: 10.1039/d0dt01397h rsc.li/dalton Photocatalytic, dye degradation, and bactericidal behavior of Cu-doped ZnO nanorods and their molecular docking analysis Mehak Rashid,† a Muhammad Ikram, *† a Ali Haider, b Sadia Naz, c Junaid Haider, c Anwar Ul-Hamid, d Anum Shahzadi e and Muhammad Aqeel a Nanostructures of Cu-doped ZnO (Cu:ZnO) were prepared with the chemical precipitation technique with an aim to enhance the photocatalytic and antibacterial properties of ZnO. Phase constitution, the presence of functional groups, optical properties, elemental composition, surface morphology and microstructure were evaluated using an X-ray diffractometer (XRD), Fourier transform infrared spec- troscopy (FTIR), UV-Vis spectrophotometer, energy dispersive X-ray spectroscopy (EDS), field emission scanning electron microscope (FESEM) and high resolution transmission electron microscope (HR-TEM), respectively. Emission spectra were obtained with a photoluminescence (PL) spectroscope whereas inter- layer d-spacing was estimated through HR-TEM. ZnO consisted of a hexagonal wurtzite structure. The crystallinity of the sample was observed to increase with increasing doping concentration. The addition of Cu to ZnO served to transform nanoclusters into nanorods as revealed during SEM analysis. Catalytic activity enhanced due to the formation of nanorods, and UV-Vis absorption spectra showed that methyl- ene blue (MB) degraded more efficiently with ZnO nanoclusters compared to the NaBH 4 reagent. In addition, the doped NPs showed enhanced bacterial efficiency for G +ve. Finally, a molecular docking study was undertaken to highlight the importance of the binding interactions of the Cu-doped ZnO nano- rods with β-lactamase and beta-ketoacyl-acyl carrier protein synthase III (FabH) as possible enzyme targets. This research indicates that Cu-doped Zn nanorods are a highly efficient photocatalyst and can be aptly employed for wastewater treatment and antibacterial applications. 1. Introduction Freshwater resources such as rivers, lakes and ponds play a crucial role in the survival and development of humans and other life forms. In many parts of the world, a lack of industry best practices and inadequate implementation of environ- mental regulations result in contamination of this crucial water supply. One such contaminant among many is indus- trial residual dyes which contain toxic and hazardous organic pollutants that tend to alter the characteristics of water causing aesthetic and health-related problems. 1–4 Water pol- luted with toxic dyes needs to be cleaned to ensure continued provision of this essential nutrient to all forms of life. Commonly used methods for dye degradation include ultra- filtration, precipitation, desalination and reverse osmosis. These techniques remove hazardous toxins, however, they may also result in the formation of certain undesirable com- pounds in the process. 5–7 Recently, photocatalysis has been reported as an extremely efficient technique for the degradation of dyes. It is also known to break down toxic substances and convert them into non-toxic products. In this process, light is permitted to fall on the surface of a semiconductor material. Light has energy equal to or greater than the band gap of the used semi- conductor (hυ ≥ E g ). As a result of this interaction between light and semiconductor, the generation of electrons (e - ) and holes (h + ) takes place. Water molecules (H 2 O) present in the surroundings are oxidized as a result of interaction with h + giving rise to hydroxyl radicals ( • OH). On the other hand, the reduction of oxygen molecules (O 2 ) by electrons e - produces superoxide anion ( • O 2 - ) and hydrogen peroxide (H 2 O 2 ). Liquid † Mehak Rashid and Muhammad Ikram are equal contributors. a Solar Cell Applications Research Lab, Department of Physics, Government College University Lahore, 54000 Punjab, Pakistan. E-mail: dr.muhammadikram@gcu.edu.pk b Department of Clinical Medicine and Surgery, University of Veterinary and Animal Sciences, Lahore 54000, Punjab, Pakistan c Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China d Center for Engineering Research, Research Institute, King Fahd University of Petroleum & Minerals, Dhahran, 31261, Saudi Arabia e College of Pharmacy, University of the Punjab, Lahore, 54000, Pakistan 8314 | Dalton Trans. , 2020, 49, 8314–8330 This journal is © The Royal Society of Chemistry 2020