Synthesis of pure and Cd-doped hydroxyapatite for the photo-catalytic degradation of Amoxicillin and Ciprofloxacin: Crystallographic characterization using XRD

Abstract

Nanosized hydroxyapatite (HAp) is considered an elementary material for artificial bone tissue engineering and the applications are expanding and one of them is the photocatalytic degradation of environmentally hazardous pollutants. In this research, HAp nanoparticles, in pure form and doped with cadmium (Cd), were synthesized using a conventional wet-chemical precipitation method. Additionally, the synthesized samples such as pure and Cd-doped HAp were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV–Vis spectroscopy. Moreover, the XRD analysis allowed for a detailed estimation of the crystallite size, assisting in their tailoring of increased photocatalytic activity. The crystallite sizes of the nano-crystallite Hap were evaluated using the Scherrer Method (SM), Williamson-Hall Method (WHM), Size-Strain Plot (SSP), Halder-Wagner Method (HWM), and Sahadat-Scherrer Method (SSM). The models confirmed the formation of nano crystallite hydroxyapatite in pure and doped form. Cadmium doping in HAp showed great photocatalytic activity for example at 150 min, 31 % amoxicillin and 52 % ciprofloxacin were degraded upon 1.5 wt % Cd doping in HAp crystal. The research demonstrated that doping Cd in HAp crystal improved photocatalytic activity towards antibiotic solution (ciprofloxacin and amoxicillin) under all test circumstances.