In situ fabrication of ternary TiO2 doped grafted chitosan/hydroxyapatite nanocomposite with improved catalytic performance for the removal of organic dyes: Experimental and systemic studies

A hetero-structured photocatalysts with enhanced mineralization capacity has been obtained significant consideration due to their improved performance in environmental purification process. Wrapping of TiO2 and hydroxyapatite with suitable biopolymer will improve the specific surface area, porosity, stability and provides enhanced degradation efficiency. Herein, TiO2 reinforced hydroxyapatite (TiO2@CS-Hpt) nanocomposite matrix was synthesized proficiently by co-precipitation technique. Here, chitosan acted as a spine in the fabrication and afforded the surface for a composite generation. Photocatalysis was the method used universally for elimination of inorganic and organic impurities from water. Herein, an integrated flexible TiO2 imprinted chitosan/hy-droxyapatite (TiO2@CS-Hpt) composite was fabricated and utilized for treating water contaminated with of Methylene Blue (MB) and Rhodamine B (RhB) dyes, via photo-degradation method. The prepared TiO2@CS-Hpt was characterized extensively using FTIR, XRD, SEM-EDX, TEM, PL and UV/Vis-DRS techniques. X-ray photo-electron spectroscopy served to confirm that the dyes underwent photo-reduction. The DRS results implies the reduction in band gap to of TiO2@CS-Hpt 2.01 eV as against 3.23 eV of TiO2. The results specified that the maximum degradation were 98.6 % and 96.7 % for MB and RhB respectively, in the experiment with the initial dye concentration 50 mg L-1, 0.1 g L-1- of photocatalyst, TiO2@CS-Hpt, pH 7 and under 120 min of light exposure. The photocatalyst reusability has been retained up to seven cycles and the practical applicability for the treatment of water/wastewater was ensured by field trial.

Automated summary

The development of hetero-structured photocatalysts by wrapping TiO2 and hydroxyapatite in a suitable biopolymer has gained significant attention for its improved performance in environmental purification processes. A TiO2 reinforced hydroxyapatite nanocomposite matrix was successfully synthesized, utilizing chitosan as a backbone for composite generation and photocatalysis was used universally for water purification. The fabricated TiO2@CS-Hpt showed enhanced degradation efficiency for Methylene Blue and Rhodamine B dyes, confirming its practical applicability in water treatment.