An Eco-Friendly Synthesis Approach for Enhanced Photocatalytic and Antibacterial Properties of Copper Oxide Nanoparticles Using Coelastrella terrestris Algal Extract

Abstract

Background

In the current scenario, the synthesis of nanoparticles (NPs) using environmentally benign methods has gained significant attention due to their facile processes, cost-effectiveness, and eco-friendly nature.

Methods

In the present study, copper oxide nanoparticles (CuO NPs) were synthesized using aqueous extract of Coelastrella terrestris algae as a reducing, stabilizing, and capping agent. The synthesized CuO NPs were characterized by X-ray diffraction (XRD), UV-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and field emission scanning electron microscopy (FE-SEM) coupled with energy-dispersive X-ray spectroscopy (EDS).

Results

XRD investigation revealed that the biosynthesized CuO NPs were nanocrystalline with high-phase purity and size in the range of 4.26 nm to 28.51 nm. FTIR spectra confirmed the existence of secondary metabolites on the surface of the synthesized CuO NPs, with characteristic Cu–O vibrations being identified around 600 cm⁻¹, 496 cm⁻¹, and 440 cm⁻¹. The FE-SEM images predicted that the enhancement of the algal extract amount converted the flattened rice-like structures of CuO NPs into flower petal-like structures. Furthermore, the degradation ability of biosynthesized CuO NPs was investigated against Amido black 10B (AB10B) dye. The results displayed that the optimal degradation efficacy of AB10B dye was 94.19%, obtained at 6 pH, 50 ppm concentration of dye, and 0.05 g dosage of CuO NPs in 90 min with a pseudo-first-order rate constant of 0.0296 min⁻¹. The CuO-1 NPs synthesized through algae exhibited notable antibacterial efficacy against S. aureus with a zone of inhibition (ZOI) of 22 mm and against P. aeruginosa with a ZOI of 17 mm.

Conclusion

Based on the findings of this study, it can be concluded that utilizing Coelastrella terrestris algae for the synthesis of CuO NPs presents a promising solution for addressing environmental contamination.

Graphical Abstract

Keywords:

• green synthesis
• CuO NPs
• photocatalysis
• antibacterial activity
• wastewater treatment

Associated Content

All experimental details are explained in the Supplementary Material 1.

Data Sharing Statement

All data generated or analyzed during this study are included in this published article. Additional data can be provided upon request from the corresponding author.

Acknowledgments

The authors thank the Department of Chemistry, Mohanlal Sukhadia University, Udaipur (Raj.), India, for providing the necessary laboratory facilities. The authors are grateful to the Department of Physics, Department of Botany, and Department of Environmental Science, Mohanlal Sukhadia University, Udaipur, for providing the XRD facility, algal culture, and water sample analysis, respectively. The authors acknowledge the facilities of Manipal University Jaipur (MUJ), India, for UV-Vis, FE-SEM coupled with EDS, and antibacterial analysis facilities.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

The authors have no competing interests to declare that are relevant to the content of this article.

Additional information

Funding

RKK and MK thank the University Grants Commission, New Delhi, India, for the UGC-Start-Up Project [No. F. 30-476/2019 (BSR)] and Fellowship [115/CSIRNETJUNE2019], respectively, for providing financial support to conduct the research work. DSR thanks the Science and Engineering Research Board, Department of Science and Technology (DST), New Delhi, for a core research grant (CRG/2019/006919).