Highly efficient methylene blue removal by TMAOH delaminated Ti3C2Tx MXene suspension and the mechanistic aspect

• Ultrathin Ti 3 C 2 T x MXene Nss suspension was synthesized by TMAOH delamination. • The MXene Nss and its composite membrane showed excellent performance on MB removal. • MB induced coagulation of MXene suspension and benefit for solid-liquid separation. • Electrostatic attraction and ion exchange are the main factors for MB removal. As a novel two-dimensional material, MXene is considered as a good candidate for pollutants removal. In this report, Ti 3 C 2 T x MXene nanosheets suspension was synthesized by intercalating and delaminating of the multi-layered Ti 3 C 2 T x using tetramethylammonium hydroxide (TMAOH). Given to its unique properties, it showed excellent performances on cationic methylene blue (MB) adsorption. The maximum adsorption capacity was figured to be 1026 mg/g at 318 K, which is much higher than most absorbents reported in previous studies. Mechanistic studies revealed that electrostatic attraction and ion exchange are the main factors for MB removal. Additionally, the Ti 3 C 2 T x MXene nanosheets composite membrane was prepared and applied to the MB removal through filtration, which showed good removal efficiency and dye water flux. The current Ti 3 C 2 T x MXene suspension should be a promising absorbent for MB removal from water.