surface of MXene. It is generally obtained by etching the MAX phase (Ti 3 AlC 2) in a HF solution or a solution that generates HF in situ. Similar to other 2D materials (such as graphene, MoS 2 , and black phosphorus, etc.), however, MXene flakes are susceptible to stacking and agglomeration due to the strong interlayer van der Waals force. This problem greatly hindered the dispersion of MXene and significantly reduce their specific surface area, thus limiting the efficient use of interface and seriously affects its performance. [6] To address this issue, a series of strategies have been adopted. For example, Gogotsi and co-workers reported that Ti 3 C 2 T x layer intercalated with cation to suppress the restacking of MXene nanosheets, thus offers high volumetric capacitance. [7] Yu and co-workers reported an MXene@polystyrene nanocomposites constructed by electrostatic assembly MXene flakes on polystyrene microspheres then compressing molding for highly efficient EMI. [8] A 3D MXene hydrogel was fabricated by using metal ions to break electrostatic repulsion force between the MXene nanosheets and serving as connectors to link the nanosheets together, which make the restacking problem of MXene be restrained and effectively increases the surface utilization of MXene. [9] These strategies can effectively inhibit the stacking of MXene and increase the layer spacing. Nevertheless, most of above methods are suffering from complex and harsh manufacturing process limitations. The poor oxidation stability is another major drawback for MXene. Due to the interaction of water and oxygen under ambient surroundings, MXene flakes are unstable and apt to oxidize. [10] It has been reported that the introduction of polyanionic salts [11] or antioxidants sodium l-ascorbate [12] in the MXene solution enables the anions to encapsulate the positively charged MXene flake edges and prevent MXene from interacting with water molecules, thereby achieving the purpose of inhibiting MXene oxidation. A stable MXene organic dispersion was reported based on simultaneous interfacial chemical grafting and phase transfer method, which has strong antioxidant properties. [13] Although the above methods can effectively suppress the oxidation of MXene, on the other hand, MXene is "contaminated" due to the introduction of other substances. Conjugated microporous polymers (CMPs) are a unique class of organic porous materials constructed by rigid conjugated 2D MXenes have attracted wide attention due to their unique chemical and physical properties. However, MXene nanosheets suffer from restacking and are susceptible to oxidation and consequently lose their functional properties which limits their applications. Thus, it is desirable to explore strategies to preserve MXene nanosheets and avoid oxidation. Herein, an effective strategy to produce MXene-based conjugated microporous polymers (M-CMPs) by covalently sandwiching MXene between CMPs using p-iodophenyl functionalized MXene as templates is demonstrated. The as-prepared M-CMPs inherit the 2D architec...

Fe3O4-Encapsulating N-doped porous carbon was synthesized for Zn–air batteries with higher energy density and better stability than Pt/C equipped devices.

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A simple and fast method for preparing MXene hydrogels is proposed by introducing protonated thionine molecules into MXene dispersion through electrostatic interaction. Such 3D hydrogel effectively suppressed restacking, oxidation, and...