A template-free method for the synthesis of porous alumina with superhigh specific surface area and large pore volume

This work demonstrates a facile organic-free and template-free approach for synthesizing spindle-like alumina with large pore volume and high specific surface area via a gas-liquid interfacial method followed by calcination. The influences of different calcination temperatures on the porous alumina were systematically studied. The possible formation mechanism of the spindle-like structures was also investigated. The results exhibited that the as-obtained amorphous alumina calcined at 300 °C had superhigh surface areas (up to 853 m2/g). Furthermore, the adsorption performance of the as-prepared amorphous alumina with high surface area was also evaluated. This spindle-like amorphous alumina showed an excellent adsorption capacity (3284 mg/g) for the removal of Congo red from aqueous solution, which indicate this porous alumina may have great potential applications in adsorption and other related areas. Spindle-like porous alumina with superhigh specific surface area were successfully synthesized for wastewater treatment via a simple and mild gas-liquid interfacial method using cheap inorganic salts without any surfactant or organic template. [Display omitted] •The porous alumina powders were synthesized by a simple gas-liquid contact method.•After calcination at 300 °C, the as-obtained alumina possess superhigh surface area (853 m2/g).•This superhigh-surface-area alumina powders presented excellent adsorption properties.