that the number of crystallites formed during heat treatment is large than that for

as-synthesized hydroxyapatite powders (Pang and Bao 2003).

The mean crystallite size of heat-treated HA, ZnHA, MgHA, FHA, and SrFHA

nanopowders at 1200 ^C was lower than 1000 ^C except for EuHA, SiHA, KSiHA,

ZnFHA, and MgSrFHA, which may be due to the decomposition of HA to β-TCP.

FHA nanopowder revealed the presence of only hydroxyapatite phase at 800 ^C and

1000 ^C, whereas β-TCP phase was observed as minor phase when heat treatment

Fig. 23.5 XRD patterns of heat-treated nanopowders (HA8 and FHA8, HA10 and FHA10, and

HA12 and FHA12: powders heat-treated at 800 ^C, 1000 ^C, and 1200 ^C)

23

Unleashing Potential of Bone Mimicking Nanodimensional Hydroxyapatites and. . .

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