Bifunctional Metal–Organic Framework-Coated Porous Hydroxyapatite Particles for Antibacterial Activity and Toluene Adsorption

The simultaneous occurrence of biological and chemical pollutants in air environments presents a significant challenge for effective air purification. Herein, we developed a bifunctional composite consisting of metal–organic framework (MOF)-coated porous hydroxyapatite (Hap) particles for simultaneous antibacterial activity and toluene adsorption. Microporous Hap particles were fabricated via an atomized aerosol reaction, followed by conformal growth of a MIL-100(Fe) layer to provide adsorption sites for aromatic volatile organic compounds. A thin MIL-100(Fe) coating layer was formed via precursor adsorption during stepwise growth metal–ligand coordination layer was additionally introduced to enhance the toluene adsorption performance of the porous Hap. The resulting composite exhibited strong antibacterial activity against Salmonella typhimurium, Pseudomonas aeruginosa, and Staphylococcus aureus, achieving greater than 99.9% bacterial reduction. In addition, the composite showed greater than 99% toluene removal within 30 min. These results demonstrate that the porous Hap framework and MOF coating provide complementary antibacterial and VOC adsorption functions within a single material platform. The developed composite offers a promising approach for the simultaneous removal of biological and chemical pollutants and may be applicable to air purification in indoor, industrial, and medical environments.