Self-assembled synthesis of urchin-like AlOOH microspheres with large surface area for removal of pollutants

Abstract

Urchin-like AlOOH microspheres with large specific surface area were successfully synthesized by a one-pot chemical induced solvothermal method. Thioglycolic acid (TGA) was used as inductive agent to fabricate AlOOH with various morphologies. Al(OH)₃–TGA clusters played an important role in the formation of AlOOH with unique spherical morphology. The preparation parameters such as reaction time, reaction temperature, and the volume ratio of deionized water to ethanol influenced the formation of AlOOH microspheres. Urchin-like AlOOH microspheres with uniform morphology were created through reaction for 20 h at either 150 or 220 °C. The specific surface area and pore-size distribution of urchin-like AlOOH were determined by N₂ absorption–desorption measurement, indicating that the AlOOH microspheres exhibited porous properties and a large specific surface area of 319.15 m² g⁻¹. A possible formation mechanism for the urchin-like AlOOH microspheres was proposed. Urchin-like AlOOH spheres prepared at 220 °C for 20 h revealed high efficiency for the removal of Congo red pollutant from waste water compared with other samples.