Controllable Synthesis of Spindle-Shaped β-FeOOH and Its Effective Adsorption for High Concentrated Congo Red

Spindle-shaped β -FeOOH nanostructures have been successfully prepared by a facile, green, and glycerol assisted solvothermal process. The spindle-like nanostructures are 25–45 nm in width and 80-180 nm in length, embracing uniform particle size. The formation mechanism of the spindle-shaped β -FeOOH, as well as the effect of glycerol and solvothermal temperatures, has been investigated in detail. The N 2 sorption results revealed that the β -FeOOH samples possess a large surface area (178.73 m 2 · g -1 ) and characteristic mesoporous structures. The XPS analysis showed that as-obtained samples have many Fe–OH groups, which is benifical for Congo red (CR) adsorption. Furthermore, the obtained samples have shown superior performance for highly concentrated CR adsorption with a maximum adsorption capacity of 714.29 mg/g. It indicates that the spindle-shaped β -FeOOH products can be potentially as a low-cost nanomaterial for efficient removal of poisonous organic pollutants from wastewater.