▎ 摘　　要

An ultrasonic-assisted preparation strategy was employed to synthesize in-situ hydroxyapatite-reduced graphene oxide nanocomposite (n-HA/rGO) as a potential biomaterial for bone regeneration under the osteoporotic condition. The results of Rietveld refinement indicated that the optimum crystallite size was 20.26 +/- 0.52 nm following the ultrasonication at 400 W for 10 min. Well-dispersed plate-shaped HA nanocrystals with the mean thickness of 25 +/- 2 nm were formed on the surface of rGO due to its anchoring tendency with calcium ions and hydrogen phosphate. By increasing the amount of power to 500 W, the intensity ratio of the D and G bands (ID/IG) increased due to the rise in the perturbation level in the rGO matrix and the chemical interactions between the rGO and HA. (c) 2020 Elsevier B.V. All rights reserved.