Luminescence and biological properties of Ag doped Dy:(ZnO–Li₂O–Na₂O–P₂O₅) glass

ABSTRACT

The melt quench technique was used to prepare phosphate-based glasses composed of ZnO–Li₂O–Na₂O–P₂O₅ which were activated with luminescent Dy³⁺ ions and doped with various concentrations of Ag. X-ray diffraction was used to confirm the formation of amorphous glass material. The glasses were characterised by density measurements, absorption spectroscopy and by photoluminescence excitation and emission scans. Four emission bands at 482 nm (blue), 573 nm (yellow), 663 nm (red) and 752 nm (red) were recorded, corresponding to transitions of Dy³⁺ ions. Antibacterial tests were made against Escherichia coli, Staphylococcus aureus and Listeria monocytogenes, while antifungal tests were performed with the yeasts Candida albicans and Cryptococcus neoformans. Doping with a low concentration of Ag enhanced the luminescent and antimicrobial properties, although higher doping levels led to the formation of metallic Ag nanoparticles and a decrease in these useful properties.

KEYWORDS:

• Phosphate glass
• silver
• dysprosium
• luminescence
• antibacterial

Acknowledgements

The authors acknowledge D. D. Ramteke for assistance in the synthesis process.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Trilok K. Pathak http://orcid.org/0000-0003-0086-8988

Hendrik C. Swart http://orcid.org/0000-0001-5233-0130

Additional information

Funding

This work was supported by the South African Research Chairs Initiative of the Department of Science and Technology and the National Research Foundation of South Africa under Grant [84415]; National Research Foundation of South Africa under Grant [93214]