Fabrication of Defect‐Engineered MOF‐801 Membrane for Efficient Dye Rejection

Although having shown great promise for efficient water treatment, rational structural design and engineering of polycrystalline MOF membranes remain rarely investigated so far. In this study, we prepared well‐intergrown MOF‐801 membranes with tailorable structural deficiencies in the framework for application in dye rejection. Of particular note, we found that the addition of formic acid as modulator led to the formation of MOF‐801 membrane with higher missing‐linker number, which was beneficial for increasing water flux with little compromise in dye rejection rate. The MOF‐801 membrane prepared in this work exhibited excellent dye rejection performance (CR rejection rate of 99.50 % and water flux of 31.69 L m−2 h−1 bar−1) as well as excellent long‐term stability. Well‐intergrown MOF‐801 membranes were presented with different defects, which showed excellent dye rejection performance by epitaxial growth. The control of the structure and function of MOF‐801 membranes by formic was presented so that their separation performances could be deliberately tailored. This strategy would promote the further development of defect engineering to improve the performance of MOF membrane.