Multifunctional capacitive deionization removal of metal ions via crumpled phosphorus-doped Ti3C2Tx MXene nanosheets

Capacitive deionization (CDI) technology shows excellent development prospects in seawater desalination and the removal of heavy metal ions from wastewater due to its high efficiency, environmental protection, and energy saving. However, the lack of suitable electrode materials with excellent performance limits the development of CDI. Herein, a crumpled phosphorus-doped Ti 3 C 2 T x MXene nanosheets (P-Ti 3 C 2 T x ) was synthesized by an in-situ phosphating strategy. The P heteroatom doping not only improves the electrical conductivity and modulates the surface properties of Ti 3 C 2 T x MXene nanosheets , but also availably alleviates the self-stacking problem of Ti 3 C 2 T x MXene nanosheets . Specifically, the P-Ti 3 C 2 T x shows excellent multifunctional removal performance for various metal ions (Na + : 61.8 mg g −1 , Pb 2+ : 84.3 mg g −1 , and Cr 3+ : 99.7 mg g −1 ). Additionally, the removal mechanism of P-Ti 3 C 2 T x is investigated by systematic characterizations and theory calculations. Therefore, this work provides new ideas for the development of multifunctional CDI electrode materials with excellent performance.