Residue-Free Orally Administered Drug Carrier Based on a Porous Aromatic Framework for Efficient Multisite Treatment.

Nowadays, oral medications are the primary method of treating disease due to their convenience, low cost, and safety, without the need for complex medical procedures. To maximize treatment effectiveness, almost all oral medications utilize drug carriers, such as capsules, liposomes, and sugar coatings. However, these carriers rely on dissolution or fragmentation to achieve drug release, which leads to drugs and carriers coabsorption in the body, causing unnecessary adverse drug reactions, such as nausea, vomiting, abdominal pain, and even death caused by allergy. Therefore, the ideal oral drug carrier should avoid degradation and absorption and be totally excreted after drug release at the desired location. Herein, a gastrointestinally stable oral drug carrier based on porous aromatic framework-1 (PAF-1) is constructed, and it is modified with famotidine (a well-known gastric drug) and mesalazine (a well-known ulcerative colitis drug) to verify the excellent potential of PAF-1. The results demonstrate that PAF-1 can accurately release famotidine in stomach, mesalazine in the intestine, and finally be completely excreted from the body without any residue after 12 h. The use of PAF materials for the construction of oral drug carriers with no residue in the gastrointestinal tract provides a new approach for efficient disease treatment.

Flexible porous organic polymers constructed using C(sp3)-C(sp3) coupling reactions and their high methane-storage capacity.

Carbon-carbon coupling is a basic design principle for the synthesis of porous organic polymers, which are widely used in gas adsorption/separation, photocatalysis, energy storage, etc. However, the C(sp3)-C(sp3) coupling reaction to construct porous organic polymers remains an important yet elusive objective due to its low reactivity and unknown side reactions. Herein, we report that nickel bis(1,5-cyclooctadiene) (Ni(COD)2), which was a famous catalyst for C(sp2)-C(sp2) coupling reactions, enables highly efficient C(sp3)-C(sp3) homo-coupling reactions to construct porous linear crystalline polymers and flexible three-dimensional porous aromatic frameworks (PAFs) under mild reaction conditions. The resulting linear polymers generated with dibromomethyl arenes have good crystallinity and high melting points (T m = 286 °C) due to controllability of reaction sites. Furthermore, the PAFs (PAF-64, PAF-65 and PAF-66) stemmed from tri-/tetra-bromomethyl arenes show high surface area (S BET = 390 m2 g-1) and high methane-storage capacity (up to 313 cm3 cm-3) because of their flexible frameworks. This work sheds new light on the construction of novel porous polymers through C(sp3)-C(sp3) coupling reactions and the development of methane-storage materials.

An integrated "rigid-flexible" strategy by side chain engineering towards high ion-conduction cationic covalent organic framework electrolytes.

In recent years, solid-state lithium metal batteries (SSLMBs) have become a new development trend, and it has become a top priority to design solid-state electrolytes (SSEs) that can rapidly and stably transport lithium ions in a variety of climatic environments. In this work, an integrated "rigid-flexible" dual-functional strategy is proposed to develop a cationic covalent organic framework (EO-BIm-iCOF) with well-defined flexible oligo(ethylene oxide) (EO) chains as an SSE for SSLMBs. As expected, the synergistic effects of the rigid cationic framework and flexible EO chains not only promote the dissociation of LiTFSI salts, but also greatly improve the transport of lithium ions, which endows LITFSI@EO-BIm-iCOF SSEs with a high Li+ conductivity of 1.08 × 10-4 S cm-1 and ionic transference number of 0.69 at room temperature. Besides, the molecular dynamics (MD) simulations have also elucidated the diffusion and transport mechanism of lithium ions in LITFSI@EO-BIm-iCOF SSEs. Interestingly, the assembled SSLMBs wherein LiFePO4 is paired with LITFSI@EO-BIm-iCOF SSEs display decent electrochemical properties at higher and lower temperatures. This work provides a great development prospect for the application of cationic COFs in solid-state batteries.

Assembly-Dissociation-Reconstruction Synthesis of Covalent Organic Framework Membranes with High Continuity for Efficient CO2 Separation.

Covalent organic frameworks (COFs), at the forefront of porous materials, hold tremendous potential in membrane separation; however, achieving high continuity in COF membranes remains crucial for efficient gas separation. Here, we present a unique approach termed assembly-dissociation-reconstruction for fabricating COF membranes tailored for CO2/N2 separation. A parent COF is designed from two-node aldehyde and three-node amine monomers and dissociated to high-aspect-ratio nanosheets. Subsequently, COF nanosheets are orderly reconstructed into a crack-free membrane by surface reaction under water evaporation. The membrane exhibits high crystallinity, open pores and a strong affinity for CO2 adsorption over N2, resulting in CO2 permeance exceeding 1060 GPU and CO2/N2 selectivity surpassing 30.6. The efficacy of this strategy offers valuable guidance for the precise fabrication of gas-separation membranes.

Enhancing Efficiency and Durability of Perovskite Solar Cells with Chlorine-Functionalized Fully Conjugated Porous Aromatic Framework.

Non-radiative recombination, caused by trap states, significantly hampers the efficiency and stability of perovskite solar cells (PSCs). The emerging porous organic polymers (POPs) show promise as a platform for designing novel defect passivation agents due to their rigid and porous structure. However, the POPs reported so far lack either sufficient stability or clear sites of interactions with the defects. Herein, two chlorine-functionalized, fully conjugated porous aromatic frameworks (PAFs) were constructed via a decarbonylation reaction. The chlorinated PAFs feature unique long-range conjugated networks bearing multiple chlorine atoms, significantly improving the photovoltaic performance and stability of doped solar cells. Combined experimental and theoretical analyses confirmed the strong passivation effects of conjugated structure to the defect through Cl sites. Specifically, PAF-159, bearing a triphenylamine moiety, demonstrated stronger Cl-Pb bonding and higher passivation efficiency due to the presence of π* anti-bonding orbitals, which elevate the HOMO energy level and facilitate Cl-Pb charge transfer. Consequently, we obtained high-performance PAF-159-doped devices with advanced PCE (24.3%), good storage stability (retaining 86% after 3000 hours), and good long-term operational stability (retaining 92% after 350 hours).

Construction of Porous Aromatic Frameworks with Specifically Designed Motifs for Charge Storage and Transport.

ConspectusPorous frameworks possess high porosity and adjustable functions. The two features conjointly create sufficient interfaces for matter exchange and energy transfer within the skeletons. For crystalline porous frameworks, including metal organic frameworks (MOFs) and covalent organic frameworks (COFs), their long-range ordered structures indeed play an important role in managing versatile physicochemical behaviors such as electron transfer or band gap engineering. It is now feasible to predict their functions based on the unveiled structures and structure-performance relationships. In contrast, porous organic frameworks (POFs) represent a member of the porous solid family with no long-range regularity. For the case of POFs, the randomly packed building units and their disordered connections hinder the electronic structural consistency throughout the entire networks. However, many investigations have demonstrated that the functions of POFs could also be designed and originated from their local motifs.In this Account, we will first provide an overview of the design and synthesis principles for porous aromatic frameworks (PAFs), which are a typical family of POFs with high porosity and exceptional stability. Specifically, the functions achieved by the specific design and synthesis of in-framework motifs will be demonstrated. This strategy is particularly intuitive to introduce desired functions to PAFs, owing to the exceptional tolerance of PAFs to harsh chemical treatments and synthetic conditions. The local structures can be either obtained by selecting suitable building units, sometimes with the aid of computational screening, or emerge as the product of coupling reactions during the synthetic process. Radical PAFs can be obtained by incorporating a persistent radical molecule as a building unit, and the rigid and porous framework may facilitate the formation of radical species by trapping spins in the organic network, which could avoid the delocalizing and recombining processes. Alternatively, radical motifs can also be formed during the formation of the framework linkages. The coupling reaction plays an important role in the construction of functional motifs like diacetylene. The highly porous, radical PAFs showed significant performance as anodes of lithium-ion batteries. To improve the charge transport within the framework, the building units and their connecting manner were cohesively considered, and the framework with a fully conjugated backbone was built up. In another case, the explicit product of the cross-coupling reaction ensured the precise assembly of two building units with electron donating and accepting abilities; therefore, the moving direction of photogenerated electrons was rationally controlled. Constructing a fully conjugated backbone or rationally designing a D-A system for charge transfer in porous frameworks introduced exciting properties for photovoltaic and photocatalysis, and their highly porous, stable frameworks improved their functional applications for perovskite solar cells and chemical productions. These investigations shed light on the designable combination of intrinsic functional motifs with highly porous organic frameworks for effective energy storage and conversion.

Anti-Eimeria tenella activity of Ethanamizuril in vitro and in vivo.

The prevalence of chicken coccidiosis in the poultry industry is a significant concern, further exacerbated by the emergence of drug-resistant coccidia resulting from the indiscriminate use of medications. Ethanamizuril, a novel triazine anti-coccidial compound, has been used to combat drug resistance. Currently, it is known that Ethanamizuril acts on the second-generation merozoites and early gametogenesis stages of Eimeria. Limited information exists regarding its impact on the early merozoites and exogenous stage of Eimeria. In the present study, the anti-coccidial properties of Ethanamizuril were evaluated both in vitro and in vivo. The in vitro experiments demonstrated that Ethanamizuril effectively inhibits the sporulation of E. tenella oocysts in a dose-dependent manner and significantly reduces the sporozoite excystation rate. Furthermore, in vivo tests revealed that treatment with 10 mg/L Ethanamizuril in drinking water significantly decreased the copy number of first-generation and secondary-generation merozoites in the chicken cecum, indicating that it can inhibit the development of whole schizonts development. Moreover, treatment with Ethanamizuril demonstrated excellent protective efficacy with an anti-coccidial index (ACI) of 180, which was manifested through higher body weight gains, lighter cecal lesion, lower fecal oocyst shedding score and reduced liver index. Collectively, this study suggests that Ethanamizuril effectively treats E. tenella infection by inhibiting both endogenous and exogenous stages development.

Confinement Synthesis of Atomic Copper-Anchored Polymeric Carbon Nitride in Crystalline UiO-66-NH2 for High-Performance CO2-to-CH3OH Photocatalysis.

Photocatalytic CO2 reduction to value-added fuels displays an attractive scenario to enhance energy supply and reduce global warming. We report herein the confinement synthesis of polymeric carbon nitride (PCN) incorporating with Cu single atoms (CuSAs) inside the crystalline UiO-66-NH2, which combines the merits of heterojunction photocatalysis and single-atom catalysis (SAC) to achieve high-performance CO2-to-CH3OH conversion. A series of spectral studies displays the formation of CuSAs@PCN inside the crystalline UiO-66-NH2. Remarkably, the ternary composite shows an excellent photocatalytic turnover frequency of 4.15 mmol·h-1·g-1 for CO2-to-CH3OH conversion. Theoretical and experimental studies demonstrate the doping of CuSAs, as well as the formation of type-II heterojunction, are causal factors to achieve CH3OH generation. The study provides new insights designing high-performance photocatalyst for CO2 conversion to fuels at atomic scale.

Donor-acceptor type triphenylamine-based porous aromatic frameworks (TPA-PAFs) for photosynthesis of benzimidazoles.

The development of efficient and recyclable photocatalysts for organic synthesis is of great interest. This study presents the synthesis of triphenylamine-based porous aromatic frameworks (TPA-PAFs) in an alternating donor-acceptor (D-A) manner. The light absorption range and the optical band gaps of TPA-PAFs are effectively tuned by changing the electron acceptor units, which further determine their photocatalytic properties. As a result, TPA-PAFs exhibit excellent catalytic performance for the photosynthesis of benzimidazoles in high yields (up to 99%), broad substrate scope (18 examples), and good recyclability (up to 10 cycles). This work provides a feasible approach toward the facile design and synthesis of efficient and stable PAF-based photocatalysts, which further broadens the application of PAFs catalytic materials in photocatalytic organic synthesis.

Porous Aromatic Frameworks Enabling Polyiodide Confinement toward High Capacity and Long Lifespan Zinc-Iodine Batteries.

Aqueous zinc-iodine batteries (AZIBs) are attracting increasing attention because of their high safety and abundance of resources. However, the performance of AZIBs is compromised by inadequate confinement of soluble polyiodides, the undesired shuttle effect, and slow reaction kinetics. In this study, a porous aromatic framework (PAF) with abundant benzene motifs and a well-organized pore structure is adopted as the iodine host, which exhibits high iodine adsorption capacity and robust polyiodide confinement. Both experimental characterizations and theoretical simulations indicate that the interactions between iodine species and the PAF-1 facilitate the redox reaction by coupling the electronic structures of the active species in the framework. A comparison of PAF-1, PAF-5, and PAF-11 also emphasizes the structural advantages of the high surface area and interconnected three-dimensional channels of PAF-1. Consequently, the I2@PAF-1 cathode can deliver a high capacity of 328 mAh g-1 at 0.5 C, outstanding rate performance, and a stable cycling life of 20 000 cycles (86 % retention at 10 C). The robust polyiodide confinement and superb electrochemical performance of Zn-I2@PAF-1 provide insights into the practical application of PAFs as excellent electrode materials for AZIBs.

Ionic Porous Aromatic Frameworks Embedding Polyoxometalates for Heterogeneous Catalysis.

Porous aromatic frameworks (PAFs) are highly promising functional porous solids known for their feasible amenability and extraordinary stability. When the framework was modified by ionic functional groups, these ionic PAFs (iPAFs) exhibited charged channels for adsorption, separation, and catalysis. However, the surface areas of ionic porous frameworks are usually lower than that of neutral frameworks, and their synthesis is limited by specific strategies and complex modification processes. To address these challenges, an intuitive route to construct ionic porous framework with high specific surface area was proposed. Herein, a multivariate ionic porous aromatic framework (MTV-iPAFs, named PAF-270) was synthesized using readily available building units with ionic functional groups through a multivariable synthesis strategy. PAF-270 exhibited hierarchical structure with the highest specific surface area among reported imidazolium-functionalized PAFs. Utilizing its physical and chemical properties, the availability for polyoxometalate loading and heterogeneous catalysis of PAF-270 were explored. PAF-270 exhibited a high adsorption capacity up to 50 % for both H3O40PW12 (HPW) and (NH4)5H6PV8Mo4O40 (V8). HPW@PAF-270 and V8@PAF-270 exhibited excellent catalytic abilities for oleic acid esterification and extractive oxidative desulfurization, respectively. Due to the stability of PAFs, these materials also showed remarkable resistance to temperature and pH changes. Overall, these results underscore the potential application of MTV-iPAFs as versatile functional porous materials.

Lignin Derived Ultrathin All-Solid Polymer Electrolytes with 3D Single-Ion Nanofiber Ionic Bridge Framework for High Performance Lithium Batteries.

The lignin derived ultrathin all-solid composite polymer electrolyte (CPE) with a thickness of only 13.2 µm, which possess 3D nanofiber ionic bridge networks composed of single-ion lignin-based lithium salt (L-Li) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) as the framework, and poly(ethylene oxide)/lithium bis(trifluoromethanesulfonyl)imide (PEO/LiTFSI) as the filler, is obtained through electrospinning/spraying and hot-pressing. t. The Li-symmetric cell assembled with the CPE can stably cycle more than 6000 h under 0.5 mA cm-2 with little Li dendrites growth. Moreover, the assembled Li||CPE||LiFePO4 cells can stably cycle over 700 cycles at 0.2 C with a super high initial discharge capacity of 158.5 mAh g-1 at room temperature, and a favorable capacity of 123 mAh g-1 at -20 °C for 250 cycles. The excellent electrochemical performance is mainly attributed to the reason that the nanofiber ionic bridge network can afford uniformly dispersed single-ion L-Li through electrospinning, which synergizes with the LiTFSI well dispersed in PEO to form abundant and efficient 3D Li+ transfer channels. The ultrathin CPE induces uniform deposition of Li+ at the interface, and effectively inhibit the lithium dendrites. This work provides a promising strategy to achieve ultrathin biobased electrolytes for solid-state lithium ion batteries.

Tuning Electron Delocalization of Redox-Active Porous Aromatic Framework for Low-Temperature Aqueous Zn-K Hybrid Batteries with Air Self-Chargeability.

Air self-charging aqueous batteries promise to integrate energy harvesting technology and battery systems, potentially overcoming a heavy reliance on energy and the spatiotemporal environment. However, the exploitation of multifunctional air self-charging battery systems using promising cathode materials and suitable charge carriers remains challenging. Herein, for the first time, we developed low-temperature self-charging aqueous Zn-K hybrid ion batteries (AZKHBs) using a fully conjugated hexaazanonaphthalene (HATN)-based porous aromatic framework as the cathode material, exhibiting redox chemistry using K+ as charge carriers, and regulating Zn-ion solvation chemistry to guide uniform Zn plating/stripping. The unique AZKHBs exhibit the exceptional electrochemical properties in all-climate conditions. Most importantly, the large potential difference causes the AZKHBs discharged cathode to be oxidized using oxygen, thereby initiating a self-charging process in the absence of an external power source. Impressively, the air self-charging AZKHBs can achieve a maximum voltage of 1.15 V, an impressive discharge capacity (466.3 mAh g-1), and exceptional self-charging performance even at -40 °C. Therefore, the development of self-charging AZKHBs offers a solution to the limitations imposed by the absence of a power grid in harsh environments or remote areas.

Rationally Designed Cyclooctatetrathiophene-Based Porous Aromatic Frameworks (COTh-PAFs) for Efficient Photocatalytic Hydrogen Peroxide Production.

Constructing stable and efficient photocatalysts for H2O2 production is of great importance and is challenging. In this study, the synthesis of three photoactive cyclooctatetrathiophene (COTh)-based porous aromatic frameworks (COTh-PAFs) in an alternating donor-acceptor (D-A) fashion is presented. In combination with a triazine-derived electron acceptor, PAF-363 exhibits high efficiency for the photosynthesis of H2O2 with production rates of 11733 µmol g-1 h-1(with sacrificial agent) and 3930 µmol g-1 h-1 (without sacrificial agent) from water and oxygen under visible light irradiation. Experimental results and theoretical calculations reveal that the charge transfer positions and the O2 adsorption sites in PAF-363 are both concentrated on COTh fragments, which facilitate the H2O2 production through the oxygen reduction reaction (ORR) pathway. This work highlights that the rational design of COTh-PAFs with consideration of D-A direction, charge transfer positions, and O2 adsorption sites provides a feasible access to efficient H2O2 production photocatalysts.

Ultrathin Free-Standing Porous Aromatic Framework Membranes for Efficient Anion Transport.

Porous aromatic frameworks (PAFs) show promising potential in anionic conduction due to their high stability and customizable functionality. However, the insolubility of most PAFs presents a significant challenge in their processing into membranes and subsequent applications. In this study, continuous PAF membranes with adjustable thickness were successfully created using liquid-solid interfacial polymerization. The rigid backbone and the stable C-C coupling endow PAF membrane with superior chemical and dimensional stabilities over most conventional polymer membranes. Different quaternary ammonium functionalities were anchored to the backbone through flexible alkyl chains with tunable length. The optimal PAF membrane exhibited an OH- conductivity of 356.6 mS ⋅ cm-1 at 80 °C and 98 % relative humidity. Additionally, the PAF membrane exhibited outstanding alkaline stability, retaining 95 % of its OH- conductivity after 1000 hours in 1 M NaOH. To the best of our knowledge, this is the first application of PAF materials in anion exchange membranes, achieving the highest OH- conductivity and exceptional chemical/dimensional stability. This work provides the possibility for the potential of PAF materials in anionic conductive membranes.

Porous organic framework membranes based on interface-induced polymerisation: design, synthesis and applications.

Porous organic frameworks (POFs) are novel porous materials that have attracted much attention due to their extraordinary properties, such as high specific surface area, tunable pore size, high stability and ease of functionalisation. However, conventional synthesised POFs are mostly large-sized particles or insoluble powders, which are difficult to recycle and have low mass transfer efficiencies, limiting the development of their cutting-edge applications. Therefore, processing POF materials into membrane structures is of great significance. In recent years, interface engineering strategies have proved to be efficient methods for the formation of POF membranes. In this perspective, recent advances in the use of interfaces to prepare POF membranes are reviewed. The challenges of this strategy and the potential applications of the formed POF membranes are discussed.

Anchoring π-d Conjugated Metal-Organic Frameworks with Dual-Active Centers on Carbon Nanotubes for Advanced Potassium-Ion Batteries.

Potassium-ion batteries (PIBs) are gradually gaining attention owing to their natural abundance, excellent security, and high energy density. However, developing excellent organic cathode materials for PIBs to overcome the poor cycling stability and slow kinetics caused by the large radii of K+ ions is challenging. This study demonstrates for the first time the application of a hexaazanonaphthalene (HATN)-based 2D π-d conjugated metal-organic framework (2D c-MOF) with dual-active centers (Cu-HATNH) and integrates Cu-HATNH with carbon nanotubes (Cu-HATNH@CNT) as the cathode material for PIBs. Owing to this systematic module integration and more exposed active sites with high utilization, Cu-HATNH@CNT exhibits a high initial capacity (317.5 mA h g-1 at 0.1 A g-1 ), excellent long-term cycling stability (capacity retention of 96.8% at 5 A g-1 after 2200 cycles), and outstanding rate capacity (147.1 mA h g-1 at 10 A g-1 ). The reaction mechanism and performance are determined by combining experimental characterization and density functional theory calculations. This contribution provides new opportunities for designing high-performance 2D c-MOF cathodes with multiple active sites for PIBs.

Boosting H+ Storage in Aqueous Zinc Ion Batteries via Integrating Redox-Active Sites into Hydrogen-Bonded Organic Frameworks with Strong π-π Stacking.

In the emerging aqueous zinc ion batteries (AZIBs), proton (H+ ) with the smallest molar mass and fast (de)coordination kinetics is considered as the most ideal charge carrier compared with Zn2+ counterpart, however, searching for new hosting materials for H+ storage is still at its infancy. Herein, redox-active hydrogen-bonded organic frameworks (HOFs) assembled from diaminotriazine moiety decorated hexaazatrinnphthalene (HOF-HATN) are for the first time developed as the stable cathode hosting material for boosting H+ storage in AZIBs. The unique integration of hydrogen-bonding networks and strong π-π stacking endow it rapid Grotthuss proton conduction, stable supramolecular structure and inclined H+ storage. As a consequence, HOF-HATN displays a high capacity (320 mAh g-1 at 0.05 A g-1 ) and robust cyclability of (>10000 cycles at 5 A g-1 ) based on three-step cation coordination storage. These findings get insight into the proton transport and storage behavior in HOFs and provide the molecular engineering strategy for constructing well-defined cathode hosting materials for rechargeable aqueous batteries.

Constructing Heterogeneous Interface by Growth of Carbon Nanotubes on the Surface of MoB2 for Boosting Hydrogen Evolution Reaction in a Wide pH Range.

Transition metal diborides represented by MoB2 have attracted widespread attention for their excellent acidic hydrogen evolution reaction (HER). Nevertheless, their electrocatalytic performance is generally unsatisfactory in high-pH electrolytes. Heterogeneous interface engineering is one of the most promising methods for optimizing the composition and structure of electrocatalysts, thereby greatly affecting their electrochemical performance. Herein, a heterostructure, composed of MoB2 and carbon nanotubes (CNTs), is rationally constructed by boronizing precursors including (NH4 )4 [NiH6 Mo6 O24 ]·5H2 O (NiMo6 ) and Co complexes on the carbon cloth (Co,Ni-MoB2 @CNT/CC). In this method, NiMo6 is boronized to form MoB2 by a modified molten-salt-assisted borothermal reduction. Meanwhile, Co catalyzes extra carbon sources to grow CNTs on the surface of MoB2 . Thanks to the successful production of the heterostructure, Co,Ni-MoB2 @CNT/CC exhibits remarkable HER performance with a low overpotential of 98.6, 113.0, and 73.9 mV at 10 mA cm-2 in acidic, neutral, and alkaline electrolytes, respectively. Notably, even at 500 mA cm-2 , the electrochemical activity of Co,Ni-MoB2 @CNT/CC exceeds that of Pt/C/CC in an alkaline solution and maintains over 50 h. Theoretical calculations reveal that the construction of the heterostructure is beneficial to both water dissociation and reactive intermediate adsorption, resulting in superior alkaline HER performance.

Continuous Ultrathin Zwitterionic Covalent Organic Framework Membrane Via Surface-Initiated Polymerization Toward Superior Water Retention.

Efficient construction of proton transport channels in proton exchange membranes maintaining conductivity under varied humidity is critical for the development of fuel cells. Covalent organic frameworks (COFs) hold great potential in providing precise and fast ion transport channels. However, the preparation of continuous free-standing COF membranes retaining their inherent structural advantages to realize excellent proton conduction performance is a major challenge. Herein, a zwitterionic COF material bearing positive ammonium ions and negative sulphonic acid ions is developed. Free-standing COF membrane with adjustable thickness is constructed via surface-initiated polymerization of COF monomers. The porosity, continuity, and stability of the membranes are demonstrated via the transmission electron microscopy (TEM), atomic force microscopy (AFM), and scanning electron microscopy (SEM) characterization. The rigidity of the COF structure avoids swelling in aqueous solution, which improves the chemical stability of the proton exchange membranes and improves the performance stability. In the higher humidity range (50-90%), the prepared zwitterionic COF membrane exhibits superior capability in retaining the conductivity compared to COF membrane merely bearing sulphonic acid group. The established strategy shows the potential for the application of zwitterionic COF in the proton exchange membrane fuel cells.