Surfactant directed synthesis of mesoporous alumina and α‐alumina single crystal

Mesoporous Al₂O₃ were positively synthesized via treatment of the freshly precipitated amorphous alumina gel using aluminium sulphate as aluminium source, and sodium dodecyl sulphate (SDS) as structure‐directing agent (SDAs). The microstructures, morphologies and textural properties of the as‐prepared materials were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM) and thermo gravimetric analysis (TG‐DTA). The calcined product at 600 °C was highly porous in nature having a BET surface area of 42 m²/g. These porous Al₂O₃ exhibits excellent adsorption performance for Congo red and the corresponding decolourisation efficiencies reached 99% in just 15 min at 27 °C. The subsequent calcined product at 1200 °C is the alpha alumina single crystal hexagonal platelets with rhombohedral crystallization.