Mesoporous silica formation on hydroxyapatite nanoparticles

[Display omitted] •The additive effect of tetraethoxysilane on HAp crystal growth was investigated.•The mesoporous silica layers were successfully formed on the HAp nanoparticles.•The BET surface area of the silica/HAp hybrid was changed with the feed Ca/P ratio.•The mesoporous silica phases interacted with the a-plane surfaces of HAp nanoparticle.•The HAp crystals grew along with the c-axis direction to be the anisotropic shapes. The additive effect of TEOS and CTAB on the HAp crystal growth and HAp/silica hybrid shape was investigated. The mesoporous silica formation on the HAp nanoparticles was successfully achieved, and the SBET and RBJH values were changed with the feed Ca/P ratio. The HAp/silica hybrids exhibited the higher SBET values with the mesopores. It was suggested that the silica phase specifically interacted with the a-plane of HAp and subsequently the HAp along with the c-axis direction to be anisotropic hybrid shapes.