A Novel Ethanol Induced and Stabilized Hierarchical Nanorods: Hydroxyapatite Nanopeanut

Abstract

Hydroxyapatite (HA) nanopeanut, hierarchical nanorods covered with nanopits on surface, was successfully synthesized via a novel ethanol induced and stabilized route. Ca(NO 3 ) 2 , H 3 PO 4 , and NaOH were used as calcium source, phosphorus source, and pH adjusting agent, respectively. X-ray diffraction analysis showed that hierarchical nanorods are well crystallized and present a pure hexagonal Ca 10 (PO 4 ) 6 (OH) 2 . Transmission electron microscopy (TEM) exhibited that the nanorods are of 50-210 nm in length and 22-52 nm in width. The nanopits of 3-12 nm in diameter in the surface were also confirmed and calculated by nitrogen adsorption/desorption isotherms, which is well consistent with TEM observation. Ethanol as the sole functional organic molecule played the roles of improving the HA crystallization, inducing the nucleation and growth of HA nanorods, as well as inducing and stablizing the nanopits in surface. The ethanol-assisted synthesis mechanism of HA nanopeanut was proposed and discussed in thermodynamics. This novel ethanol-assisted route is green, facile, efficient, low-cost, and surfactant-free and may be useful for the synthesis of other hierarchical materials.W. Zhang-contributing editor Manuscript No. 36254.

Calcium phosphate coatings for marble conservation: Influence of ethanol and isopropanol addition to the precipitation medium on the coating microstructure and performance

“…Even if a decrease in crystallinity of the new CaP has been reported in some cases [32,33], ethanol is thought to enhance the CaP crystallinity [34][35][36] and to increase the crystallite size, because it increases the supersaturation in the medium [37]. Moreover, ethanol has been reported to intensify the interactions between the ions in the solution, because of the decrease in the dielectric constant [32].…”

“…Compared to the case of no ethanol addition (PO4 3-concentration of 0.22 mg/L), the amount increases to 0.32 and 0.76 mg/L for ethanol additions of 10 and 30 vol%, respectively (Table 3). Moreover, a further aspect that is expected to enhance CaP formation in a water-ethanol solution is the fact that OH -groups in the ethanol molecule are adsorbed to the surface of the CaP nuclei, thus decreasing their interface energy [35]. Combined with the higher supersaturation in water-ethanol systems (compared to the aqueous systems) [35,39], this leads to a decrease in the critical nucleation free energy, so that CaP nuclei are easier to form in water-ethanol systems [35].…”

Synthesis, characterization, in vitro bioactivity and antimicrobial activity of magnesium and nickel doped silicate hydroxyapatite

“…Hydroxyapatite (HA, Ca 10 (PO 4 ) 6 (OH) 2 ) is a synthetic biomaterial resembling the composition of mammalian hard tissue and as a result it is one of the most frequently used bone graft material [1]. Mineral component of mammalian bone is nonstoichiometric in nature and is predominantly composed of Ca, P and O with trace amount of various ions like Na þ , SiO 4 À 4 , Mg 2 þ , SO 2 À 4 , Sr 2 þ , Ni 2 þ , F À , etc.…”

Novel cupric acetate self‐induced, stabilized cupric oxide mesoporous nanosheets via a reflux‐hydrothermal method

“…In our previous studies, the organic amphiphilic molecules or ions rather than OH − were proved to be functional template for inducing hierarchical structures. This also can be supported by the other groups’ studies .…”

“…Inspired from our previous findings, small molecule (ethanol) can realize efficient tailoring and control of hierarchical structures via a combined synthesis method, novel cupric acetate self‐induced, stabilized CuO mesoporous nanosheets (CuO‐MNS) were synthesized via a reflux‐hydrothermal method in this paper. The synthetic mechanism was proposed in thermodynamics based on calculation and Gibbs theory.…”