Decorating MXene with tiny ZIF-8 nanoparticles: An effective approach to construct composites for water pollutant removal

MXenes have attracted increasing research enthusiasm owing to their unique physical and chemical properties. Although MXenes exhibit exciting potential in cations adsorption due to their unique surface groups, the adsorption capacity is limited by the low specific surface area and undeveloped porosity. Our work aims at enhancing the adsorption performance of a well-known MXene, Ti₃C₂T_x, for methylene blue (MB) by decorating tiny ZIF-8 nanoparticles in the interlayer. After the incorporation of ZIF-8, suitable interspace in the layers resulting from the distribution of tiny ZIF-8 appears. When employing in MB, the adsorption capacity of composites can reach up to 107 mg·g⁻¹ while both ZIF-8 (3 mg·g⁻¹) and Ti₃C₂T_x (9 mg·g⁻¹) show nearly no adsorption capacity. The adsorption mechanism was explored, and the good adsorption capacity is caused by the synergistic effect of ZIF-8 and Ti₃C₂T_x, for neither of them is of suitable interspace or surface groups for MB adsorption. Our work might pave the way for constructing functional materials based on the introduction of nanoparticles into layered materials for various adsorption applications.