Title : Development of bio-waste engineered multi-ion hydroxyapatite as a high-performance material for airborne pollutant capture
Abstract:
The increasing concentration of airborne pollutants and industrial CO₂ emissions has intensified the demand for sustainable, materials-based environmental remediation strategies. In this study, a nano multi-ion doped hydroxyapatite (HAp) material was synthesized using naturally derived calcium precursors such as eggshells and coral stones. The HAp matrix was doped with Ag⁺, Sr²⁺, Zn²⁺, and F⁻ ions to enhance its surface reactivity, thermal stability, and adsorption efficiency. The synthesized powders were systematically characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM–EDX), particle size analysis (PSA), and Brunauer Emmett–Teller (BET) surface area analysis. The structural and morphological analyses confirmed high crystallinity, uniform dopant incorporation, and a mesoporous framework favourable for CO₂ adsorption under ambient conditions. The material exhibited superior adsorption performance compared to conventional TiO₂-based photocatalysts, maintaining efficiency in both light and dark environments. The utilization of waste derived natural sources underscores the sustainability and economic feasibility of the synthesis process. Overall, the developed multi-ion doped HAp demonstrates excellent potential as a coating material for environmental applications such as exhaust filters and reactor chambers, offering a dual function of carbon capture and air purification.
