Engineered/designer hierarchical porous carbon materials for organic pollutant removal from water and wastewater: A critical review

Hierarchical porous carbon (HPC) materials have found advanced applications in energy storage, adsorption, and catalysis in recent years. The HPC can be synthesized from a vast range of inexpensive carbon precursors, and contain unique structural features, such as nano-scale dimension, high porosity, high surface area, and tunable pore surfaces. These materials hold immense potential for removing contaminants from water and wastewater. However, this area is severely under-explored yet. In this review, we have discussed the recent advances of synthesis, modification, and application of HPC for the removal of pollutants from water, especially focusing on organic pollutants. Owing to their intrinsic hydrophobic nature and unique interconnected porous structure, HPC demonstrates a high affinity to hydrophobic organic contaminants, which can be enhanced many folds by target-specific chemical activation. Successful high-performance removal of contaminants by pristine and modified HPC includes plastic-derived (e.g. bisphenol A), pharmaceutical (e.g. antibiotics), dye (e.g. methylene blue) and pesticide micro-pollutants. Future research is warranted to find optimal and effective HPC synthesis and modification methods for further improving their ability to remove aqueous organic contaminants as a low-cost and energy-inexpensive remediation technology.