Graded pore defect UiO-66 material and preparation method thereof

The invention belongs to the technical field of preparation of organic pore materials, and particularly relates to a graded pore defect UiO-66 material and a preparation method thereof. Based on the thermal stability difference of two ligands of terephthalic acid and trisubstituted benzene series, in the thermal treatment process, terephthalic acid in the material structure can be kept stable, and the trisubstituted benzene series can be pyrolyzed, so that the trisubstituted benzene series can be effectively and selectively removed, and a mesoporous defect structure is left. Compared with existing methods for constructing mesoporous defects such as a Soxhlet extraction method and a mixed ligand hydrolysis method, the method provided by the invention is simple to operate, the obtained product is high in purity and high in yield, and the prepared UiO-66 material not only retains an original microporous structure, but also generates mesoporous level defects, so that the material has graded pore properties; in ad