polymerization process, the crosslinking of monomers on crystalline solid surfaces, liquid-liquid interfaces, or liquid-gas interfaces often requires harsh reaction conditions, for instance, high vacuum, strict equipment requirements and severe solvent system, [17,39] which makes the synthesis process difficult to control and impractical for large-scale preparation. Compared with interfacial polymerization, existing 2D materials such as graphene, [19][20][21]23,26,31,35,36,40,41] molybdenum disulfide, [27,37,42] and MXene [43,44] as sacrificial substrates reduce the requirement for reaction equipment and own mild reaction conditions, however, the functional modification and removal of 2D substrates lead to complicated experimental procedures, hindering the research on the functionality and applicability of the materials.Elaborately construction of well-defined mesopores in 2D polymers is becoming as an appealing goal, enabling 2D polymers with interconnected pore networks, large specific surface areas, and more active sites, thus enhancing the application performance of the materials. [18] Until now, widely used ways to conduct mesoporous structures into 2D polymers often involve nanocasting method or molecular self-assembly method. The nanocasting method utilizes the pre-designed structure and the rigidity of SiO 2 template to achieve the synthesis of 2D mesoporous polymers. [23,24,35] Nevertheless, the additional etching process is laborious and low yielding. In comparison, the molecular self-assembly strategy using block copolymers as templates is a more promising method of preparing 2D mesoporous polymers. [19,25,[36][37][38]43] For example, Feng and Mai et al. reported the one-step synthesis of 2D mesoporous polypyrrole and polydopamine employing block copolymers polystyrene-b-poly(ethylene oxide) (PS-b-PEO) and P123 (poly(ethylene oxide) 20 -block-poly(phenylene oxide) 70 -blockpoly(ethylene oxide) 20 ) respectively. [43,45] However, the currently developed 2D mesoporous polymers are very limited owing to the following issues: a) Few types of precursor molecules and 2D substrates are available for polymers. b) The often lack of matched driving forces between polymer precursors, micelles, and 2D substrates leads to difficulties in tuning their co-assembly behavior, ultimately resulting in dense and nonporous structures. c) The framework of formed polymer is unstable and easily destroyed during the process of removing the block copolymer. Therefore, exploring Two-dimensional (2D) mesoporous polymers, combining the advantages of organic polymers, porous materials, and 2D materials, have received great attention in adsorption, catalysis, and energy storage. However, the synthesis of 2D mesoporous polymers is not only challenged by the complex 2D structure construction, but also by the low yield and difficulty in controlling the dynamics of the assembly during the generation of mesopores. Herein, a facile multi-dimensional molecular self-assembly strategy is reported for the preparation of 2D mesoporous polydiam...