Fabrication of a reusable Ti3C2Tx MXene/ZnO@zinc alginate hydrogel for highly efficient and selective phosphate removal

Nano-Zinc oxide (ZnO) shows great potential for phosphate adsorption, but its tendencies to aggregate and lack of selectivity significantly impact adsorption efficiency. The synthesis of Ti3C2Tx MXene/ZnO complexes efficiently disperses ZnO, thereby enhancing selectivity, while encountering challenges in recovery. In this study, Ti3C2Tx MXene/ZnO-embedded zinc crosslinked alginate hydrogel beads (MXZA) were synthesized by solutionphase and ionic cross-linking methods as a highly efficient, selective, and reusable phosphate adsorbent. MXZA exhibited a maximum adsorption capacity of up to 86.67 mg/g of phosphate, and showed excellent adsorption selectivity in complex solutions (e.g., Cl-, NO3-, and SO42-). In short, the MXZA gel adsorbent has a wide application perspective in the effective and selective removal of phosphate from wastewater.