One-pot template-free synthesis of mesoporous boehmite core–shell and hollow spheres by a simple solvothermal route

Uniform-sized and monodispersed boehmite core–shell and hollow spheres have been successfully synthesized using a template-free solvothermal route. The experimental parameters such as reaction duration, the trisodium citrate amounts and solvents are shown to play important roles in the formation of the AlOOH core–shell and hollow spheres. X-ray diffraction, Fourier transform IR, thermal gravimetric analysis, N2 adsorption/desorption, scanning electron microscopy, transmission electron microscopy, and high-resolution TEM were used to characterize the products. The results show that the prepared polycrystalline hollow spheres are composed of well-aligned AlOOH nanowires and have an orthorhombic structure. Finally, a dissolution–renucleation mechanism was proposed for the formation of boehmite hollow structures.