Structural and morphological analysis of zinc incorporated non-stoichiometric hydroxyapatite nano powders

In this study, Zn incorporated non-stoichiometric hydroxyapatite (nHAp) was synthesized via precipitation method and effect of the incorporation of Zn (fraction: 2, 4, 6 and 8 mol-%) on the microstructure of nHAp was studied by XRD, FTIR analysis and SEM-EDS techniques. The formation of nHAp was confirmed by XRD and FTIR those showed that no secondary phase was formed through the Zn incorporation. The SEM studies also revealed that particles were formed in nano-metric size (30-60 nm). It was found that crystallite and particle size of Zn incorporated nHAp gradually decreased up to 6 mol-%, and started to increase while the Zn fraction reached up to the 8 mol-% and hence the morphology of the aggregated products was also changed. It can be concluded that the incorporation of Zn cations cause to form nHAp phase. Furthermore, the nHAp microstructure has deviated from stoichiometric condition by incorporation of more Zn cations.Keywords: Microstructure; Nanopowder; Non-Stoichiometric Hydroxyapatite; Zn Incorporatio

Structural and morphological analysis of zinc incorporated non-stoichiometric hydroxyapatite nano powders

ABSTRACT In this study, Zn incorporated non-stoichiometric hydroxyapatite (nHAp) was synthesized via precipitation method and effect of the incorporation of Zn (fraction: 2, 4, 6 and 8 mol-%) on the microstructure of nHAp was studied by XRD, FTIR analysis and SEM-EDS techniques. The formation of nHAp was confirmed by XRD and FTIR those showed that no secondary phase was formed through the Zn incorporation. The SEM studies also revealed that particles were formed in nano-metric size (30-60 nm). It was found that crystallite and particle size of Zn incorporated nHAp gradually decreased up to 6 mol-%, and started to increase while the Zn fraction reached up to the 8 mol-% and hence the morphology of the aggregated products was also changed. It can be concluded that the incorporation of Zn cations cause to form nHAp phase. Furthermore, the nHAp microstructure has deviated from stoichiometric condition by incorporation of more Zn cations

Comparative photodecolorization of red dye by anatase, rutile (TiO2), and wurtzite (ZnO) using response surface methodology

Treatment of dye pollution containing C.I. Acid Red 14 (AR14) by a coupled photocatalytic process was studied. Titanium dioxide, in the form of anatase and rutile, and zinc oxide, were used as photocatalysts. The investigated photocatalysts were Aldrich-produced nanopowders with crystallites of a mean size 20-30 nm and a specific surface area of about 50 m(2)/g. A comparison of TiO2(anatase), TiO2(rutile), TiO2(a,r), and ZnO for the decolorization of the AR14 solution was performed. Results showed that color removal followed the decreasing order of TiO2(a,r), ZnO > TiO2(a,r) > TiO2(a), ZnO > TiO2(r), ZnO >TiO2(a,r) > TiO2(a) > ZnO > TiO2(r). Response surface methodology (RSM) was employed to assess the individual and interactive effects of the 4 main independent parameters in the photocatalytic process. Analysis of variance showed a high coefficient of determination (R-2 = 0.9396) and satisfactory prediction second-order regression. The optimum initial amounts of TiO2(a), TiO2(r), ZnO. and dye and the reaction time were found to be 84 ppm, 23 ppm, 86 ppm, 20 ppm, and 48 min, respectively. It was demonstrated that RSM with suitable 2D and 3D graphs was a suitable method for finding the interactions between parameters, identifying the main parameters, and optimizing the operating conditions