Synthesis of zinc oxide/bismuth oxide nanocomposite photocatalyst for visible light-assisted degradation of synthetic dyes and antibacterial application.

Contamination of water resources by artificial coloring agents and the increasing incidence of bacterial illnesses are two significant environmental and public health issues that are getting worse day by day. Traditional treatment techniques frequently fail to address these problems adequately in a sustainable and environmental friendly way. In response, our study presents a novel photocatalyst that demonstrates superior photodegradation capability and antibacterial qualities in catering the above issues. Sonochemical synthesis route was adopted to synthesize the nanocomposite of zinc oxide/bismuth oxide (ZnO-Bi ₂ O ₃ ) along with pure ZnO and Bi ₂ O ₃ . X-ray diffraction investigation was performed to analyze the crystallographic structure and confirmed the formation of the composite. High-resolution transmission electron microscopic analysis showed that the particle size of the composite to be in 20 to 55 nm range with the formation of heterojunction at ZnO/Bi ₂ O ₃ interface. Fourier transformed infrared spectroscopic and micro Raman studies of the nanocomposite sample helped to detect the presence of stretching vibrations linked with Zn and Bi ions. X-ray photoelectron spectroscopy study revealed the chemical constitution and electronic states of the nanocomposite sample displaying the Zn 2p, Bi 4f, and O 1 s spectral lines. Investigation on the photocatalytic efficiency of the samples was done and the results showed an appreciable increase in photodegradation efficiency for the composite sample in degrading methylene blue (93.24%) and Congo red (92.47%) dyes in 180 min. The effect of pH, photocatalyst amount, and dye concentration on the efficiency of degradation was also been examined. Two primary causes of the enhanced performance of the composite are the generation of hydroxyl radicals (OH•) and the suppression of carrier recombination which is initiated by the synergistic combination of the two metal oxides in the nanocomposite. The nanocomposite sample was found to be stable and reusable for its effective use in environmental cleanup. By using the disk diffusion process, the antibacterial potential of the samples was analyzed and it was discovered that the nanocomposite showed an exceedingly superior antibacterial performance than the pristine samples in preventing the growth of two strains of bacteria, i.e., Escherichia coli and Staphylococcus aureus.
Competing Interests: Declarations. Ethics approval: This is an observational study. The Centurion University Research Ethics Committee has confirmed that no ethical approval is required. Consent to participate: Not applicable as no research was conducted involving human subjects. Consent for publication: Not applicable as no research was conducted involving human subjects. Competing interests: The authors declare no competing interests.
(© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)