Morphological Evolution of Hydroxyapatite Particles in the Presence of Different Citrate:Calcium Ratios
authors Santos, C; Almeida, MM; Costa, ME
nationality International
journal CRYSTAL GROWTH & DESIGN
keywords HYDROTHERMAL SYNTHESIS; CITRIC-ACID; NANOPARTICLES; PHOSPHATE; SIZE; NANOCRYSTALS; ADSORPTION; PRECURSOR; TEMPLATE; DELIVERY
abstract This work is focused on the potential role of citrate-derived species as tailoring agents for the morphology of hydroxyapatite particles during their synthesis. Under hydrothermal conditions (T = 180 degrees C), precursor solutions with different initial citrate:calcium molar ratios (R) allow the nucleation and growth of hydroxyapatite particles whose final morphology shows a significant dependence on the initial citrate amount and growth time. Increasing R from 3:1 to 7:1 causes the morphology to evolve from needlelike- and rodlike-shaped nanoparticles toward larger microparticles with hedgehoglike or bundlelike aspects that are composed of assembled primary units. A strong decay of the specific surface area from 55 m(2)/g for nanometric particles (R = 3:1) down to 17 m(2)/g for microparticles (R = 7:1) also corroborates the morphological evolution. The evolution of the particle morphology is accompanied by citrate chemistry changes. As confirmed by Fourier transform IR spectroscopy and thermal analysis, citrate ions undergo thermal degradation during the synthesis process to generate smaller carboxylate-based species adsorbed on the particles' surfaces. The concentration of such species and their mode of coordination to the hydroxyapatite surface is R-dependent. Accordingly, it is suggested that these organics interplay differently with the growth of the developing hydroxyapatite structures, thereby affecting the final particle morphology.
publisher AMER CHEMICAL SOC
issn 1528-7483
year published 2015
volume 15
issue 9
beginning page 4417
ending page 4426
digital object identifier (doi) 10.1021/acs.cgd.5b00737
web of science category Chemistry, Multidisciplinary; Crystallography; Materials Science, Multidisciplinary
subject category Chemistry; Crystallography; Materials Science
unique article identifier WOS:000360867300029
  ciceco authors
  impact metrics
journal analysis (jcr 2017):
journal impact factor 3.972
5 year journal impact factor 3.880
category normalized journal impact factor percentile 77.120
dimensions (citation analysis):
altmetrics (social interaction):



 


Apoio

1suponsers_list_ciceco.jpg