A novel surface patterning nanorod: Hydroxyapatite nano labyrinth, promoted, induced and stabilized by tetrahydrofuran

A novel surface patterning nanorod (hydroxyapatite nano labyrinth, HANL), covered with labyrinthine nano-grooves on surface, was successfully synthesized with the assistance of tetrahydrofuran (THF). THF as the sole organic molecule not only promoted HA crystal growth, but also induced and stabilized the hierarchical nanorod. XRD results indicated that HANLs were of high phase purity and were well crystallized. SEM and TEM images showed that HANLs were of the length of 75-425 nm and the width of 20-85 nm, and were of 1-9-nm wide grooves covering over the surface which were also confirmed by the N-2 adsorption analysis. The synthetic mechanism was proposed and explained in thermodynamics combined with theoretic calculations. This novel hierarchical HANLs may have great potential applications in bone replacement materials, composites, adsorbents, carriers, etc. This THF assisted synthetic strategy is green, low-cost, efficiently and surfactant-free, and may be useful in surface patterning other functional materials.