Amino-functionalized hierarchical porous SiO2-AlOOH composite nanosheets with enhanced adsorption performance

Hierarchical porous SiO 2 -AlOOH composite nanosheets (HPSA) with a three-dimensional (3D) structure were prepared from two-dimensional (2D) layered mineral kaolinite (A1 2 Si 2 O 5 (OH) 4 ) via a template-free structural reorganization method. The obtained material was subjected to homogeneous and effective amino-functionalization by grafting it with (3-aminopropyl) triethoxysilane. Owing to the enhanced 3D hierarchical meso-macroporous structure containing highly dispersed protonated amino groups ( NH 3 + ), the as-prepared amino-functionalized HPSA (NH 2 -HPSA) showed unique adsorption performance towards the congo red anionic dye. It provides feasibilities to fabricate other functional hierarchical porous materials from clay minerals, which can offer potential applications in adsorption, separation, catalysis and other environmental remediation fields.