Enhanced photocatalytic and antibacterial activities of novel Ag-HA bioceramic nanocatalyst for waste-water treatment

Hydroxyapatite (HA), the most common bioceramic material, offers attractive properties as a catalyst support. Highly crystalline mono-dispersed silver doped hydroxyapatite (Ag-HA) nanorods of 60 nm length was developed via hydrothermal processing. Silver dopant offered enhanced chemisorption for crystal violet (CV) contaminant. Silver was found to intensify negative charge on the catalyst surface; in this regard enhanced chemisorption of positively charged contaminants was accomplished. Silver dopant experienced decrease in the binding energy of valence electron for oxygen, calcium, and phosphorous using X-ray photoelectron spectroscopy XPS/ESCA; this finding could promote electron-hole generation and light absorption. Removal efficiency of Ag-HA nanocomposite for CV reached 88% after the synergistic effect with 1.0 mM H2O2; silver dopant could initiate H2O2 cleavage and intensify the release of active OH radicals. Whereas HA suffers from lack of microbial resistance; Ag-HA nanocomposite demonstrated high activity against Gram-positive (S. aureus) bacteria with zone of inhibition (ZOI) mm value of 18.0 mm, and high biofilm inhibition of 91.1%. Ag-HA nanocompsite experienced distinctive characerisitcs for utilization as green bioceramic photocatalyst for wastewater treatment.

Automated summary

Hydroxyapatite (HA), the most common bioceramic material, is a promising catalyst support. Highly crystalline and mono-dispersed silver doped hydroxyapatite (Ag-HA) nanorods of 60 nm length were successfully synthesized through hydrothermal processing. The silver dopant improved chemisorption for crystal violet (CV) contaminant and enhanced the negative charge on the catalyst surface, leading to enhanced chemisorption of positively charged contaminants. Ag-HA nanocomposite showed high activity against Gram-positive bacteria and inhibited biofilm formation, making it a potential green bioceramic photocatalyst for wastewater treatment.