Recognition of the surface characteristics and electrical properties of a nanocrystalline hydroxyapatite synthesized from Pila globosa shells for versatile applications

Abstract

This paper describes the synthesis and characterization of a nanocrystalline hydroxyapatite (HAp) bioceramics using dead biomass of Pila globosa shells. The high calcium carbonate content (94.76%) analyzed by inductively coupled plasma atomic emission spectroscopy confirmed the snail shell to be an appropriate precursor for HAp synthesis. The presence of CO32− groups (B-site) in the HAp particle was evident from Fourier-transform infrared spectroscopy data. Brunauer–Emmett–Teller surface area analysis revealed the surface area and average pore diameter of HAp particle to be 146.372 m2g−1 and 40.82 nm, respectively. The most intense (211) plane in X-ray diffraction pattern supported the nanocrystalline nature of HAp with crystallite size of 9 nm. The field emission scanning electron microscopy analysis of HAp powder confirmed its particles to be agglomerated with average size of 32.84–38.24 nm. The point of zero charge determined by pH analysis was found to be 8.37. The Ca/P ratio was envisaged to be 1.66 on a par with biological material. The interfacial layer purity of HAp was established by X-ray photoelectron spectroscopy. The investigation on the dielectric properties and AC conductivity supported the material to have low dielectric loss (1.73) and high dielectric constant (296.6). The frequency dependence of AC conductivity validated the power law and impendence analyses demonstrated the material to be grain type. Overall studies indicate that the synthesized HAp could be a potent material for versatile applications.