Porous Polymer Research Articles

3D Printing-Induced Phase Transition in Ferroelectric Porous Polymer Coatings for Stable Zinc Anodes.

The abundant availability of zinc and its environmentally friendly properties have increasingly drawn attention to the potential of aqueous zinc-ion batteries (AZIBs). However, their development is hindered by the formation of zinc dendrites and severe side reactions during charge/discharge cycles. In this work, a novel strategy is introduced to address these challenges by constructing a ferroelectric porous PVDF-HFP protective layer (PH-ZF) on the zinc anode surface using 3D printing technology. This approach not only simplifies the fabrication process but also achieves a high content of β-phase PVDF-HFP without the need for post-treatment. The ferroelectric porous polymer layer effectively regulates ion concentration distribution on the zinc anode surface, promoting uniform Zn2+ deposition. As a result, symmetric batteries exhibit cycle lifetimes of 1200 and 2000 h at current densities of 0.5 and 1.0 mA cm-2, respectively. Furthermore, full batteries with MnO2 cathodes maintained a discharge specific capacity of ≈88.3 mA g-1 after 1000 cycles at a current density of 1.0 A g-1, in contrast to bare zinc electrodes, which retain only 51 mAh g-1 under the same conditions. This method offers a promising approach for enhancing zinc anode protection and advancing ZIB performance.

Ultrasmall Bismuth Nanoparticles Supported Over Nitrogen-Rich Porous Triazine-Piperazine Polymer for Efficient Catalytic Reduction.

The development of inexpensive and reusable nanocatalysts to convert the hazardous pollutant 4-nitrophenol (4-NP) into a valuable platform chemical 4-aminophenol (4-AP) is quite demanding due to environmental and public health concerns. Herein, we report a facile strategy for the preparation of supported Bi nanoparticles (NPs) over the surfaces of nitrogen-rich porous covalent triazine-piperazine-3D nanoflowers (BiNPs@3D-NCTP). SEM and TEM image analysis suggested 3D-flower-like morphology of the materials. The powder X-ray diffraction (PXRD) analysis also confirmed the loading of Bi NPs. N2 sorption analysis suggested BET surface areas of 663 and 364 m2g-1 for the 3D-NCTP and BiNPs@3D-NCTP materials, respectively. The large surface area, bimodal pores and 3D nanoflower architecture enable uniform loading of Bi nanoparticles, while its nitrogen-rich functionality stabilizes and acts as a capping agent restricting further nanoparticle expansion. BiNPs@3D-NCTP showed a 99.85% conversion for the 4-NP to 4-AP within four minutes. The normalized rate constant of 38.3 min-1 mg-1 of BiNPs@3D-NCTP catalyst for reducing of 4-NP suggested its superior catalytic efficiency. Nitrogen-rich functionality activates the catalytic site to accelerate the reaction, while bimodal pores can promote diffusion of reactant molecules. After five catalytic cycles, the nanocatalyst showed high chemical stability and negligible activity loss.

Design and Assembly of Conductive Covalent Organic Frameworks for Proton Exchange Membrane Application

AbstractTo develop proton exchange membranes (PEMs) with robust structure stability and remarkable proton conductivity and explore their application in PEMs fuel cells have significant implications for realizing reduced carbon emission and environmental pollution. Covalent organic frameworks (COFs), as crystalline porous polymer material composed of organic monomers and connected by covalent bond, possess specific framework, inherent porosity, adjustable functional group and eminent thermal/chemical structure stability. Therefore, COFs display prominent superiorities in constructing rigid ordered proton transfer channels and improving fuel cell performance long‐term durability. In this review, the proton conduction properties of extrinsic proton‐conductive COFs (incorporating carriers into the pore), intrinsic proton‐conductive COFs (introducing conductive groups on the backbone) and combined extrinsic/intrinsic proton‐conductive COFs in the form of pressed pellets are discussed in detail. Meanwhile, proton‐conductive COFs related PEMs, including COFs‐related polymer‐based composite membranes, COFs‐based composite membranes and self‐supporting COFs membranes are also systematically summarized. In addition, the existing challenges are analyzed and future outlooks are addressed.

Vinylene-Linked Covalent Organic Frameworks for Visible-Light-Promoted Selective Oxidation of Styrene in Water.

Vinylene-linked COFs, as an emerging class of crystalline porous polymers, have been regarded as ideal heterogenous photocatalysts due to their ordered structure, tailored pore size, outstanding stability and fully π-conjugated structure. Unfortunately, their photocatalytic performances are usually impeded by high exciton binding energy and unsatisfactory exciton dissociation efficiency. Herein, the authorsbroke through this dilemma by arrangement of complementary donor-acceptor (D-A) pairs within the COF skeleton to improve charge transfer/separation. Two vinylene-linked COFs (TMT-BT-COF and TMT-TT-COF) are synthesized by Aldol condensation using highly photoactive thienothiophene and benzothiazole groups as donor and electron-deficient triazine units as acceptor. Photochemical/electrochemical studies as well as DFT calculation suggest that these D-A type vinylene-linked COFs endow high charge transfer efficiency and low charge recombination. As a result, both of them demonstrate remarkably catalytic activity in the oxidation of styrene to benzaldehyde with molecular oxygen, with an exceptionally high conversion rate (≥92%) and selectivity (≥90%). Intriguingly, in the presence of NaHCO3, the above COFs could photocatalyze epoxidation styrene in water, and the styrene oxide selectivity reached 53%. This work elucidates the prominent capability of vinylene-linked COFs in the photocatalytic transformation of organic compounds in aqueous media, which may pave a new avenue for their future development.

Triphenylamine-Based Conjugated Microporous Polymers as the Next Generation Organic Cathode Materials.

This paper presents a study on a novel porous polymer based on triphenylamine (LPCMP) as an excellent cathode material for lithium-ion batteries. Through structural design and a scalable post-synthesis approach, improvements in intrinsic conductivity, practical capacity, and redox potential in an organic cathode material is reported. The designed cathode achieves a notable capacity of 146mAhg⁻¹ with an average potential of 3.6V, using 70% active material content in the electrode. Additionally, through appropriate structural design, the capacity can increase to 160mAhg-1. Even at a high current density of 20Ag⁻¹ (360C), the cathode maintains a capacity of 74mAhg⁻¹, enabling full charge within 10 s. A high specific energy density of 569Whkg⁻¹ (at 0.1Ag⁻¹) is combined with a very high power density of 94.5kWkg⁻¹ (at 20Ag⁻¹ corresponding to a specific energy density of 263Whkg⁻¹) surpassing the power density of graphene-based supercapacitors. It exhibits highly stable cyclic performance across various current densities, retaining almost 95% of its initial capacity after 1000 cycles at 5.5C. This work presents a significant breakthrough in developing high-capacity, high-potential organic materials for sustainable, high-energy, and high-power lithium-ion batteries.

Heterogenization of a Dinuclear Cobalt Molecular Catalyst in Porous Polymers via Covalent Strategy for CO 2 Photoreduction with Record CO Production Efficiency

Heterogenization of a Dinuclear Cobalt Molecular Catalyst in Porous Polymers via Covalent Strategy for CO ₂ Photoreduction with Record CO Production Efficiency

A new Conjugated mesoporous polymer as fluorescence sensor for the detection of nerve agent simulant dimethyl chlorophosphonate via specific nucleophilic substitution reaction

Conjugated micro/mesoporous polymers (CMPs) represent a category of porous organic materials formed via covalent bonds. Here, DAC-TFP CMP was synthesized using 3,6-diaminocarbazole (DAC) and 2-hydroxy-1,3,5-benzenetricarbaldehyde (TFP) as building blocks. DAC-TFP CMP is a porous conjugation polymer with remarkable thermal and chemical stability. DAC-TFP CMP suspension demonstrates selective "on-off" fluorescence response towards nerve agent simulant dimethyl chlorophosphonate (DMCP) in 1,4-dioxane with exceptionally low detection limits. DMCP and DAC-TFP CMP undergo a nucleophilic substitution reaction, leading to the formation of an N-P bond between N atom on carbazole of DAC-TFP CMP and P atom of DMCP. The new polymer DAC-TFP CMP@DMCP has electron donor-acceptor structure and the fluorescence quenching can be ascribed to the intramolecular charge transfer (ICT) from DAC-TFP CMP unit to DMCP group, as supported by XPS results and DFT calculation. Upon the addition of DMCP to the 1,4-dioxane suspension of DAC-TFP CMP, a subtle blue shift is observed in both the fluorescence emission spectra and UV-vis absorption spectra, providing further validation of the ICT mechanism. DAC-TFP CMP shows excellent recoveries in detecting DMCP in both soil and pesticide samples containing mesotrione and atrazine, highlighting its strong potential as a reliable chemosensor for DMCP detection and analysis.

Selective separation of polyphenols with a novel azo porous organic polymer: Ultrahigh adsorption capacity and superfast adsorption rate

For the first time, a novel porous organic polymer (POP), namely Cin-POP, was constructed under normal temperature and pressure using less toxic basic fuchsin and natural cinnamic acid. Cin-POP was synthesized through the diazo-coupling reaction between the diazonium salts of basic fuchsin and cinnamic acid. The FT-IR spectra and XPS analysis prove the successful construction of the Cin-POP, and the BET analysis demonstrates the high-surface-area (166.42–202.56 m2 g−1) and suitable pore sizes (11.00–18.63 nm). Owing to the advantages of porous structures, abundant aromatic groups, good thermal stability, and good dispersity, Cin-POP exhibits remarkable adsorption rates and capacities towards polyphenols, including procyanidine and rutin. Especially for procyanidine, the extraction efficiency can arrive at nearly 98.1 % after 2.5 min adsorption, and the pseudo-second-order rate constant (k2) of Cin-POP is 0.0257 g mg−1 min−1. The maximum adsorption capacities of Cin-POP towards procyanidine and rutin are 2500.00 mg g−1 and 1814.83 mg g−1, outpacing all reported adsorbents. In addition, Cin-POP can selectively adsorb polyphenol among the mixtures of polyphenols and alkaloids. More importantly, Cin-POP can be used for polyphenols separation from complex cinnamon extract. All the above advantages make Cin-POP comparable porous adsorbent for polyphenol separation.

Porous polymers embedded with iron carbon enhanced densified activated sludge formation and wastewater treatment

Municipal wastewater treatment plants in China face significant challenges in effectively removing pollutants from low-strength wastewater with a low carbon-to-nitrogen (COD/N) ratio. This study proposes a novel approach incorporating porous polymers embedded with iron-carbon (PP-IC) into an activated sludge system to enhance treatment. The PP-IC accelerated the formation of densified activated sludge (DAS), characterized by small particle sizes (<200 μm), excellent settleability (sludge volume index: 61 mL/g), and improved pollutant removal efficiency, with total nitrogen and total phosphorus removal rates increasing by 14.4 % and 57.4 %, respectively. DAS formation was achieved within 7 days and stabilized after 42 days. The enrichment of microorganisms, including unclassified_f_Caldilineaceae, Dechloromonas, and Candidatus Accumulibacter, further enhanced pollutant removal. Additionally, Fe2+, Fe3+ and hydroxyl radical (·OH) produced by iron-carbon micro-electrolysis supported DAS formation. Microbial interactions with the iron shavings sustained the long-term stability of the micro-electrolysis process. This synergistic mechanism significantly improved pollutant removal in wastewater treatment.

Low-temperature rapid fabrication of crosslinked poly(quaterphenyl piperidine) membrane for anion exchange membrane water electrolyzers

While nonsolvent-induced phase separation (NIPS) is widely recognized as an established method for creating porous polymer membranes, this study uniquely employs a nonsolvent to produce a dense, nonporous membrane instead. Specifically, the membranes were rapidly fabricated at low temperatures using dimethyl sulfoxide (DMSO), a high-boiling-point solvent, and water as the nonsolvent. We successfully prepared a series of crosslinked poly(quaterphenyl piperidine) (PQP-BM) network membranes with high crosslinking degrees (up to 47.2 %). By combining a hydrophobic extended polyaromatic backbone with a hydrophilic piperidine-based crosslinker, we achieved distinct microphase separation, which enhanced ion transport, dimensional stability, and thermal and mechanical properties compared to the linear uncrosslinked membranes. The optimized AEM exhibited exceptional mechanical strength (tensile strength >63 MPa), high ion conductivity (151.5 mS cm⁻¹ at 80 °C), and excellent alkaline durability. In single-cell water electrolyzer tests, the PQP-BM membrane demonstrated a remarkable current density of 3.99 A cm⁻² at 2.0 V in 1 M KOH at 50 °C, outperforming the commercial FAA-3–50 membrane by 126 %. This study highlights the potential of the energy-efficient NIFF process as a scalable method for producing advanced AEMs for energy conversion applications.

Stability of Ionogels upon Contact with Water: Effect of Polymer Matrix Hydrophobicity and Ionic Liquid Solubility

New composite materials (ionogels) have been obtained based on imidazolium ionic liquids immobilized in highly porous polymers, i.e., polyamide 6,6 (nylon 6,6) and low-density polyethylene. A method has been proposed for determining the rate of ionic liquid removal from an ionogel upon contact with water, with this method being based on continuous measuring the conductivity of an aqueous phase. The results of the conductometric measurements have been confirmed by high-performance liquid chromatography data. It has been shown that the stability of ionogels upon contact with water is determined by both the hydrophobicity of a polymer matrix and the solubility of an ionic liquid in water. The highest degree of ionic liquid removal (more than 80%) has been observed for composites based on porous polyamide 6,6 (hydrophilic matrix) and dicyanimide 1-butyl-3-methylimidazolium (completely miscible with water). Ionogels based on lowdensity polyethylene (hydrophobic matrix) and bis(trifluoromethylsulfonyl)imide 1-butyl-3-methylimidazolium (poorly soluble, 1 wt %, in water) have shown the highest stability (washout degree of no more than 53% over 24 h). The method proposed for analyzing the rate of ionic liquid dissolution in water has been used to discuss the mechanism of this process.

Unveiling Local Dynamics of a Triptycene-Based Porous Polymer by Solid-State NMR

Unveiling Local Dynamics of a Triptycene-Based Porous Polymer by Solid-State NMR

The influence of ZIF-L in a microbial fuel cell (MFC) cathode for oxygen reduction reaction (ORR).

Microbial fuel cells (MFCs) utilize the metabolic activities of microorganisms, through which the chemical energy is directly converted into electrical energy. Bacteria produce electrons by means of oxidation of organic/inorganic substrates within the MFCs. Metal organic frameworks (MOFs) that are porous coordination polymers have gained much interest in the field of efficient catalysts due to their unique characteristics. The utilization of MOF catalysts for oxygen reduction reaction (ORR) in the MFC cathode is one of the most remarkable research areas in material science. MOF (zeolitic imidazole framework-leaf like, ZIF-L) decorated cathode system was employed for the first time in MFC to monitor the improvement in performance by taking advantages of both electrocatalytic activity and porosity of MOFs for the utilization of bioelectrons for ORR. Analysis of ORR performance of ZIF-L/carbon black (CB) composite cathode demonstrated that ZIF-L containing cathode system had an improved ORR activity compared to MFC cathode materials in the literature. The remarkable current density value of 2.1mAcm-2 and the maximum power density value of 1,462 mW m-2 at room temperature revealed that ZIF-L decorated cathode is an excellent alternative for efficient reduction of oxygen in MFCs.

Construction of stable triazine porous organic polymer nanofiltration membrane for selective separation: The role of substrate on the membrane formation and separation performance

Porous organic polymers (POPs) have been regarded as potential candidates for high-performance membrane building blocks ascribed to their robust structure, tunable pore size, and high surface area. Normally, the POPs membrane possesses a POPs selective layer on the porous substrate for its real application. Numerous efforts have been paid to manipulate the POPs selective layer to enhance the separation performance, however, except from providing mechanical strength, the role of substrates in the formation and separation performance of POPs membrane receives less attention. In this work, we employed a systematic study to reveal the role of substrates in the governing POPs membrane formation by choosing substrates with diverse properties. The relationship between the properties of substrate (e.g., pore size, porosity, roughness, hydrophilicity, and surface functional groups) and the assembly structure of POPs membranes was in-detail analyzed. We found that the hydrolyzed polyacrylonitrile substrate induced a better assembly of POPs nanoparticles. Its rough surface and carboxylic functional groups created Van der Waals interactions and hydrogen bonding interactions to reinforce interfacial adhesion between the substrate and POPs selective layer, which facilitated the formation of intact and defect-free POPs membranes. The resulting POPs membrane displayed a high water permeance of 121.3 L m-2h−1 bar−1 with a congo red rejection of 98.9 %. Moreover, benefiting from the robust interfacial interactions between POPs selective layer and the substrate, the POPs membrane enabled itself to maintain structure stability under harsh environments, such as acidic, alkaline, and organic solvents. This work gives new insights to producing robust and high-performance POPs membranes.

MOFs and MOF‐Based Composites for the Adsorptive Removal of Ciprofloxacin

AbstractIn spite of greater efforts to address antibiotic resistance, Ciprofloxacin (CIP) buildup in the aqueous medium continues to rise. The negative effects of CIP on the environment can be minimized through a comprehensive understanding of the technological advancements in removal techniques. The exploration of adsorbents like metal–organic frameworks (MOFs), activated carbon, porous organic polymers, etc., have found major usage in the adsorptive removal of antibiotics to tackle contamination. This study aims to compare the MOF‐based adsorbents and provide a guide to developing such materials for the successful removal of CIP. The isotherm models of the adsorbents are studied using Langmuir, Freundlich, Temkin, and Sips isotherms. Furthermore, pseudo‐second‐order, pseudo‐first order, intra‐particle diffusion, and Elovich models are used to study the kinetic models. The major mechanisms of adsorption, such as π–π interactions, H‐bonding, electrostatic interactions, hydrophobic interactions, and pore filling, are also analyzed. This study contributes to the future scope for the development of these MOFs for further exploration and applications in environmental remediation.

Selective Oxygen Activation by Integrating Dual Photosensitizers in Conjugated Porous Polymers and Microenvironments Manipulation for High‐Performance Water Purification and H2O2 Production

Selective Oxygen Activation by Integrating Dual Photosensitizers in Conjugated Porous Polymers and Microenvironments Manipulation for High‐Performance Water Purification and H₂O₂ Production

Molecular Imprinting as a Tool for Exceptionally Selective Gas Separation in Nanoporous Polymers.

The alarming rise in atmospheric CO2 levels, primarily driven by fossil fuel combustion and industrial processes, has become a major contributor to global climate change. Effective CO2 capture technologies are urgently needed, particularly for the selective removal of CO2 from industrial gas streams, such as flue gas and biogas, which often contain impurities like N2 and CH4. In this study, we report the design and synthesis of novel molecularly imprinted polymers (MIPs) using 4-vinylpyridine (4VP) and methacrylic acid (MAA) as functional monomers, and thiophene (Th) and formaldehyde (HC) as molecular templates. The MIPs were specifically engineered to create selective molecular cavities within a nanoporous polymer matrix for the efficient capture of CO2. By adjusting the molar ratios of the template to functional monomers, we optimized the molecular imprinting process to enhance CO2 selectivity over N2 and CH4. The resulting MIPs exhibited outstanding performance, with a maximum CO2/N2 selectivity of 153 at 25 bar and CO2/CH4 selectivity of 25.3 at 1 bar, significantly surpassing previously reported porous polymers and metal-organic frameworks (MOFs) under similar conditions. Furthermore, we conducted heat of adsorption studies, which revealed the strong and selective interaction of CO2 with the imprinted cavities, confirming the superior adsorption properties of the synthesized MIPs. The study demonstrates that molecular imprinting can effectively enhance both CO2 capture capacity and selectivity, providing a cost-efficient and scalable solution for industrial CO2 separation and purification processes.

Highly crystalline nanorods pyrene-based covalent organic framework artificial solid electrolyte interface accelerated interface Li+ regulation on lithium anode

The detrimental effects of heterogeneous Li deposition and aeolotropic Li dendrite propagation critically hamper its serviceability of Li metal batteries. The exploitation of neutral multifunctional porous polymer artificial SEI is imperative to modulate interfacial ionic transfer behavior. Herein, we propose a strategy based on dual-functional nanorod-shaped covalent organic frameworks (COF) to accelerate Li+ diffusion and mitigate lithium dendrite growth by creating an artificial solid electrolyte interface (SEI) layer. As anticipated, the immobilized high-polarity –OH and −CN- groups, along with the porous channel facilitates, facilitate uniform Li+ flux distribution and rapid Li+ migration. Additionally, the highly conjugated nature of the pyrene moiety not only enhances the plane π-π stacking crystallinity of TFDH-COF, but contributes positively to Li+ and repelling TFSI−. The combination of comprehensive ex-situ/in-situ characterizations and DFT calculations have unraveled the underlying mechanisms on the reductive Li mitigation energy barrier and enhancive Li+ transfer ability. In contrast with bare Li, the resultant TFDH-COF@Li electrode demonstrates the elevated reversibility of Li+ utilization, slight polarization, dendrite-free interface and prolonged cyclic performance in Li|Cu, Li|Li, and Li-based full cells operated at rigorous current densities. Those unswerving evidences enlighten the feasibility of engineering the neutrality COF layer to get rid of adverse disordered Li proliferation.

Construction of carbon nanotube-multifunctional porous ionic polymer core–shell nanocomposite for efficient conversion of carbon dioxide under co-catalyst free conditions

Metalated porous ionic polymers featuring multiple active sites show significant potential for carbon dioxide (CO2) fixation. However, general and efficient strategies to enhance their catalytic efficiency still remain to be developed. Herein, carbon nanotube-multifunctional ionic polymer core–shell composite (CNT@P(TBr-Py)-ZnBr2) was easily prepared by a solvothermal radical copolymerization strategy, followed by metallization with ZnBr2. Characterization revealed that the synthesized composite exhibited a distinct core–shell tubular nanostructure, with CNT serving as the core, and multifunctional polymer containing Lewis acid (Zn), nucleophilic Br¯ and CO2-philic triazine groups as the shell. Furthermore, the composite displayed broad pore size distribution and large average pore size. Impressively, CNT@P(TBr-Py)-ZnBr2 delivered an outstanding catalytic efficiency in the cycloaddition of CO2 to epichlorohydrin, surpassing the control catalysts poly(triazine-based vinyl ionic liquid) (PTBr), bipyridine-functionalized porous ionic polymer (P(TBr-Py), and ZnBr2 metalated P(TBr-Py) (P(TBr-Py)-ZnBr2) by factors of 5.4, 5.8, and 1.3, respectively. At 140 °C, a high turnover frequency (TOF) of 11174 h−1 and a 93.4 % yield of target cyclic carbonate were achieved in the absence of any additional co-catalyst. This exceptional catalytic performance of CNT@P(TBr-Py)-ZnBr2 can be mainly attributed to its unique core–shell structure, along with the synergistic catalytic effect of its multifunctional active sites. Also, the reaction can proceed smoothly under near-ambient conditions (30 °C, 1 bar CO2), though a longer reaction time was required. Additionally, CNT@P(TBr-Py)-ZnBr2 demonstrated a wide range of substrate compatibility and excellent recycling stability. This work therefore presents a viable approach for designing efficient and multifunctional ionic polymer-based catalysts for CO2 fixation.

Metalation of porphyrin units in a porous organic polymer stabilizing its anodic cycling performance in lithium-ion battery

Organic materials have attracted tremendous interest as electrodes materials for lithium-ion battery, however, they still suffer from intractable problems including inherent low electronic conductivity, poor cycling stability and high solubility in electrolyte etc. Herein, a porphyrin-based porous organic polymer (POP) is employed to serve as anode material by virtue of its good insolubility, unique π-π interaction and abundant active sites. The POP electrode exhibits a high specific capacity of 584 mAh g−1 at 100 mA g−1 originated from fast redox activity while unfortunately undergoes a severe capacity fading during long-term cycles. It is found that the metalation of porphyrin moiety in POP by Ni2+ (Ni-POP) enables an excellent cycling stability of 380 mAh g−1 with a capacity retention of 99 % for 500 cycles. We revealed that porphyrin unit is decomposed from the cleavage of the C-N/C=N bonds in porphyrin units, while Ni coordination stabilizes porphyrin units during fast redox process as affirmed by ex situ X-ray photoelectron spectroscopy. The easy fabrication, low-cost and excellent performance make Ni-POP great potential as anode material for lithium-ion battery.