Microwave hydrothermal synthesis of boehmite hollow microspheres

Abstract The boehmite (γ-AlOOH) hollow microspheres were synthesized after 120 min reaction time at 150 °C for the first time via a microwave hydrothermal route, using Al2(SO4)3 aqueous solution and urea as raw materials and amphiphilic copolymer of P(St)-b-P(HEA) as structure-directing agent. The final product was characterized by techniques of X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscope (SEM). The microscope analysis revealed that the boehmite (γ-AlOOH) hollow microspheres were around 1–2 μm in diameter and a shell thickness of approximately 200 nm. To investigate the influencing factors and formation mechanism of the as-obtained boehmite hollow microspheres ultra-fine powders, samples subjected to different reaction durations were also studied by SEM. A self-assembly morphology evolution mechanism was proposed based on the experimental facts.