Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity

Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling.

High-Performance Na-Ion Storage of S-Doped Porous Carbon Derived from Conjugated Microporous Polymers

Na-ion batteries(NIBs)have attracted considerable attention in recent years owing to the high abundance and low cost of Na.It is well known that S doping can improve the electrochemical performance of carbon materials for NIBs.However,the current methods for S doping in carbons normally involve toxic precursors or rigorous conditions.In this work,we report a creative and facile strategy for preparing S-doped porous carbons(SCs)via the pyrolysis of conjugated microporous polymers(CMPs).Briefly,thiophene-based CMPs served as the precursors and doping sources simultaneously.Simple direct carbonization of CMPs produced S-doped carbon materials with highly porous structures.When used as an anode for NIBs,the SCs exhibited a high reversible capacity of 440 mAh g?1 at 50 mA g?1 after 100 cycles,superior rate capability,and excellent cycling stability(297 mAh g?1 after 1000 cycles at 500 mA g?1),outperforming most S-doped carbon materials reported thus far.The excellent performance of the SCs is attributed to the expanded lattice distance after S doping.Furthermore,we employed ex situ X-ray photoelectron spectroscopy to investigate the electrochemical reaction mechanism of the SCs during sodiation-desodiation,which can highlight the role of doped S for Na-ion storage.

Conjugated microporous polymer membranes for chemical separations

Conjugated microporous polymers(CMPs) are a unique class of porous organic materials, which are constructed with π-conjugation structures leading to intrinsic micropores. The CMPs properties such as high surface area, intrinsic and rich micropores, interlocking and rigid structure, extensive π-conjugation and tunable band-gap, chemical and thermal stability, together with tailored functionalities, contribute to its abundant potential for application in fields such as photocatalysis, optoelectronics, energy storage, and chemical sensors. Recently, CMPs have gained importance in the field of membranes for chemical separation. In this review, we briefly discuss the historical development of CMPs, followed by a detailed description of the progress in state-of-the-art design, preparation, and application of CMPs in membranes. Additionally, we provide inference on the future prospects of CMPs as membranes.

Gas‐phase fluorination of conjugated microporous polymer microspheres for effective interfacial stabilization in lithium metal anodes

Lithium(Li)metal anodes have attracted extensive attention due to their ultrahigh theoretical capacity and low potential.However,the uneven deposition of Li near the unstable electrode/electrolyte interfaces leads to the growth of Li dendrites and the degradation of active electrodes.Herein,we directly fluorinate alkyne-containing conjugated microporous polymers(ACMPs)microspheres with fluorine gas(F_(2))to introduce a novel fluorinated interlayer as an interfacial stabilizer in lithium metal batteries.Using density functional theory methods,it is found that as-prepared fluorinated ACMP(FACMP)has abundant partially ionic C–F bonds.The C–F bonds with electrochemical lability yield remarkable lithiophilicity during cycling.The in situ reactions between the active C–F bonds and Li ions enable transfer of lithium fluoride microcrystals to the solid electrolyte interphase(SEI)layers,guaranteeing effective ionic distribution and smooth Li deposition.Consequently,Li metal electrodes with the fluorinated interlayers demonstrate excellent cycling performances in both half-batteries and full cells with a lithium bis(trifluoromethanesulfonyl)imide electrolyte as well as a nonfluorinated lithium bis(oxalate)borate electrolyte system.This strategy is highly significant in customizable SEI layers to stabilize electrode interfaces and ensure high utilization of Li metal anodes,especially in a nonfluorinated electrolyte.

De novo synthesis of bifunctional conjugated microporous polymers for synergistic coordination mediated uranium entrapment

This work reports a de novo synthesis of novel bifunctional conjugated microporous polymers(CMPs)exhibiting a synergistic-effect involved coordination behavior to uranium.It is highlighted that the synthetic strategy enables the engineering of the coordination environment within amidoxime functionalized CMP frameworks by specifically introducing ortho-substituted amino functionalities,enhancing the affinity to uranyl ions via forming synergistic complexes.The CMPs exhibit high Brunauer-Emmett-Teller(BET)surface area,well-developed three-dimensional(3D)networks with hierarchical porosity,and favorable chemical and thermal stability because of the covalently cross-linked structure.Compared with the amino-free counterparts,the adsorption capacity of bifunctional CMPs was increased by almost 70%,from 105 to 174 mg/g,indicating evidently enhanced binding ability to uranium.Moreover,new insights into coordination mechanism were obtained by in-depth X-ray photoelectron spectroscopy(XPS)analysis and density functional theory(DFT)calculation,suggesting a dominant role of the oxime ligands forming a 1:1 metal ions/ligands(M/L)coordination model with uranyl ions while demonstrating the synergistic engagement of the amino functionalities via direct binding to uranium center and hydrogen-bonding involved secondary-sphere interaction.This work sheds light on the underlying principles of ortho-substituted functionalities directed synergistic effect to promote the coordination of amidoxime with uranyl ions.And the synthetic strategy established here would enable the task-specific development of more novel CMP-based functional materials for broadened applications.

Truxene-based Conjugated Microporous Polymers via Different Synthetic Methods

Four truxene-based conjugated microporous polymers(Tr-CMPs)were prepared via different synthetic methods and their structure-property relationships were studied.The polymer networks have high Brunauer-Emmett-Teller(BET)specific surface areas ranging from 554 m^2·g^–1to 1024 m^2·g^–1.Pore sizes of the CMPs with different linkers are mainly located between 0.60 and 1.96 nm.Among all the Tr-CMPs,TrCMP4 has the highest BET surface area of 1024 m^2·g^–1and exhibits the highest H2 uptake of 0.88 wt%.Tr-CMP2 prepared by Suzuki-Miyaura coupling reaction has the highest photoluminescence quantum yields(PLQYs)of 13.06% and CO2 uptake of 6.25 wt%.

Selective adsorption of metronidazole on conjugated microporous polymers

Conjugated microporous polymers(CMPs) have recently received extensive attention in oil/organic solvent-water separation field as a kind of ideal porous absorbents with tunable porosity, large surface areas, and super-hydrophobicity. However, reports on the application of CMPs in adsorption of hydrophilic contaminants from water are very few. In this work, we studied the adsorption of metronidazole(MNZ), a polar antibiotic, by two kinds of CMPs. The adsorption characteristics of MNZ by the CMPs, including adsorption kinetics, mechanism, and isotherm parameters were calculated. The adsorption kinetics of MNZ was well expressed by the pseudo-second-order model, and the adsorption process was found to be mainly controlled by film diffusion. The adsorption isotherm data agreed well with the Langmuir isotherm model, and the values of free energy E indicated that the adsorption nature of MNZ on the CMPs was physisorption. Increasing dispersion degree of the CMPs in MNZ solution resulted in greater adsorption. This work may provide fundamental guidance for the removal of antibiotics by CMPs.

Catalyst-free nitro-coupling synthesis of azo-linked conjugated microporous polymers with superior aqueous energy storage capability

Developing methods to construct conjugated microporous polymers(CMPs)with desirable structures is a crucial undertaking.However,obtaining azo-CMPs with extended azaacene cores is immensely challenging.Herein,we disclose the facile synthesis of diquinoxalino[2,3-a:2',3'-c]-phenazine-core CMP(3Qn-CMP;core diameter,∼1.6 nm)via the one-step hydrothermal homocoupling of nitro monomers in a mixture solution of N,N-dimethylformamide(or N,N-dimethylacetamide)and water(1:3,v/v).A 3Qn-CMP/rGO hybrid is readily prepared from CMP spheres(diameter,0.5-1.5µm)anchored on reduced graphene oxide(rGO)nanosheets(∼3 layers)by synergizing the one-pot synthesis of(rGO)for intercalation and self-assembly.The highly porous hybrid features dual redox active sites with azo and imine linkages and efficient charge conduction.3Qn-CMP and 3Qn-CMP/rGO exhibit outstanding energy storage capacity,current density tolerance(1-50 A g^(−1)),and long-term cycling stability in aqueous acidic electrolytes.3Qn-CMP and 3Qn-CMP/rGO also produce high specific capacitances of 615.4 and 847.8 F g^(−1),respectively,at 1 A g^(−1).Approximately 99.1%of this capacitance can be retained over 50,000 continuous charge/discharge cycles at 50 A g^(−1).To the best of our knowledge,our hybrid outperforms most organic molecules or CMP-/rGO-based composites reported in the literature in terms of capacitance and cycling durability.This work provides a general strategy to access a new library of CMPs and hybrids with multilevel elaborate architectures tailored for target applications,such as electrochemical energy storage and catalysis.

Redox-active conjugated microporous polymers as electron-accepting organic pseudocapacitor electrode materials for flexible energy storage

Efficient energy storage devices,i.e.pseudocapacitors,are being intensively pursued to address the environmental and energy crises.Most high-performance pseudocapacitors are based on inorganic materials,while organic materials with broader synthetic tunability have attracted increasing interest.Despite recent progress,electron-deficient(n-type)organic pseudocapacitive materials for flexible energy storage are highly demanded yet remain largely unexplored.Here a novel set of n-type perylene diimide(PDI)based conjugated microporous polymers(CMPs),namely,CMP-1,CMP-2 and CMP-3,have been created to integrate excellent desirable characteristics as organic pseudocapacitor electrode materials for flexible energy storage.In light of electron-accepting redox-active sites,hierarchically porous structures,as well as amide-linked networks,the PDI-CMPs electrodes displayed n-type pseudocapacitive behaviors with high capacity(139-205 F g^(-1)at 0.5 A g^(-1)),wide and negative biases(-1.0 to 0 V vs.Ag/AgCl),and long cycling stability.CMP-3 consisting of tetraphenylmethane three-dimensional(3D)building block and PDI units demonstrates not only higher capacitance but also better performance stability because of the higher specific surface area and faster diffusion kinetics as compared to its counterpart CMP-1.Asymmetric supercapacitors(SCs)based on CMP-3 and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT/PSS)exhibited wider potential window(1.8 V)and higher capacitance(17.4 m F cm^(-2))compared with symmetric SCs based on PEDOT/PSS electrodes.Notably,CMP-3 also demonstrates attractive potentials as the anode for rechargeable Li-ion batteries.The study sheds light on the fundamental understanding of the key structural parameters that determine their electrochemical and transport properties,thus opening a new door for the rational design of efficient and stable n-type organic electrode materials for flexible energy storage applications.

Conjugated microporous polymers for near-infrared photothermal control of shape change

Herein,a facile and highly efficient synthetic method to prepare organic photothermal materials with high photo-stability and outstanding photothermal performance is reported.Through direct polymerization of commercial aromatic monomers in the presence of anhydrous aluminium chloride and dichloromethane,four kinds of conjugated microporous polymers(CMPs)were obtained.Detailed structural analysis confirmed that the resultant CMPs possessed abundant micropores with an extendedπ-conjugated skeleton.Under near-infrared(NIR)light irradiation(808 nm,1.0 W cm−2),all the CMPs showed fast heating-up behavior with their maximum temperatures higher than 150℃.Moreover,the efficiency of photothermal conversion(η)of the CMPs was found to increase linearly with the increase in the number of conjugated benzene rings within the monomer.Poly-TPE from tetraphenylethylene(TPE)and Poly-TP from o-terphenyl(TP)showed highηvalues of over 47%.Poly-TPE was additionally used as a photothermal filler to remotely and spatially control the shape recovery of thermal-sensitive shape memory polymers(SMPs),while its introduction(1 wt%)had little influence on the thermal and mechanical properties of the polymer matrixes.Owing to their excellent NIR photothermal performance as well as a one-step synthetic preparation,these CMPs may be promising photothermal materials for practical applications.

Hyper-crosslinked Conjugated Microporous Polymers with Increased Micropores Promotes Confining Polymerization for Electromagnetic Absorption Application

Conjugated microporous polymers have excellent skeleton structures but poor electrical conductivity limits their applications in microwave absorption.To solve this problem,a strategy of molecular expansion and confining polymerization is proposed in this work to synthesize conductive hyper-crosslinked conjugated microporous polymer.The topology of the conjugated microporous polymer is changed into a three-dimensional skeleton structure with high specific surface area by using molecular expansion technique,and the controlled growth of polypyrrole in the channel constructs a unique network structure.The balance of excellent composite backbone structure,proper conductivity,attenuation capability and impedance matching enable the material to exhibit electromagnetic wave absorption performance.As a result,with low filler loading of 10 wt%,a strongest reflection loss of-52.68 d B and a maximum effective bandwidth of 5.76 GHz.Additionally,CST simulations of the radar scattering cross section have been carried out to verify the excellent material properties.This study provides new concepts for new conductive polymers and broadens the application of hyper-crosslinked conjugated microporous polymer in the field of electromagnetic wave absorption.

Tetra-armed conjugated microporous polymers for gas adsorption and photocatalytic hydrogen evolution

Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solvents tested and are thermally stable. The pyrene-containing polymer of PrPy with the rigid pyrene unit shows a higher Brunauer-Emmet-Teller specific surface area of 1219m2g-1 than the tetraphenylethylene-containing polymer of PrTPE （770m2g 1）, which leads to a high CO2 uptake ability of 3.89mmolg I at 1.13bar/273K and a H2 uptake ability of 1.69wt% at 1.13bar/77K. The photocatalytic hydrogen production experiments revealed that PrPy also shows a better photocatalytic performance than PrTPE due to the higher conjugation degree and planar structure, the broader UV-visible （UV-Vis） absorption, the lower photoluminescence lifetime, and the higher specific surface area.

Metal-free synthesis of pyridyl conjugated microporous polymers with tunable bandgaps for efficient visible-light-driven hydrogen evolution

Conjugated microporous polymers(CMPs) with tunable bandgaps have attracted increasing attention for photocatalytic hydrogen evolution. However, the synthesis of CMPs usually needs expensive metal-based catalysts. Herein, we report a metal-free synthetic route to fabricate pyridyl conjugated microporous polymers(PCMPs) via a condensed polymerization between aldehyde and aryl ketone monomers. The PCMPs show widely tunable specific surface areas(347–418 m^(2)/g), which were controlled via changing the used monomers. The PCMPs synthesized using monomers of dialdehyde and diacetylbenzene(diacetylpyridine) in the presence of pyridine exhibited the highest visible-light driven hydrogen evolution rate(9.56 μmol/h). These novel designed PCMPs provide wide adaptability to current materials designed for high-performance photocatalysts in different applications.

Metal-free Synthesis of Pyridyl Conjugated Microporous Polymers for Photocatalytic Hydrogen Evolution

Developing efficient,stable and sustainable photocatalysts for water splitting is one of the most significant methods for generating hydrogen.Conjugated microporous polymers,as a new type of organic semiconductor photocatalyst,have adjustable bandgaps and high specific surface areas,and can be synthesized using diverse methods.In this work,we report the design and synthesis of a series of pyridyl conjugated microporous polymers(PCMPs)utilizing polycondensation of aromatic aldehydes and aromatic ketones in the presence of ammonium acetate.PCMPs with different chemical structures were synthesized via adjusting monomers with different geometries and contents of nitrogen element,which could adjust the bandgap and photocatalytic performance.Photocatalytic hydrogen evolution rate(HER)up to 1198.9μmol·h^(-1)·g^(-1) was achieved on the optimized polymer with a specific surface area of 312 m^(2)·g^(-1) under UV-Vis light irradiation(A>320 nm).This metal-free synthetic method provides a new avenue to preparing an efficient photocatalyst for hydrogen evolution.

Polyfunctional Conjugated Microporous Polymers for Applications in Direct C—H Arylation of Unactivated Arenes and Aqueous Adsorption of Aromatic Amines

Salen-porphyrin-based conjugated microporous polymers(CMPs)have been demonstrated to be an attractive material platform for predesigned structures and promising applications.Herein,a new salen-porphyrin-based conjugated microporous polymer(SP-CMP-L)was solvothermally prepared by porphyrin-forming condensation reaction of pyrrole and salen-dialdehyde derivative.The SP-CMP-L was characterized by spectroscopy technologies,and also exhibited excellent thermal and chemical stability.The porosity of SP-CMP-L was examined by N2 adsorption/desorption isotherms.The BET specific surface area of the CMP material was calculated to be 290.4 m^2/g with the pore volume of 0.19 cm^3/g.The microstructure property of the resulting material was further evaculated by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The SP-CMP-L with salen and porphyrin multidentate coordination sites was proposed to serve as an initiator to promote the cross-coupling between aryl halides with unactivated arenes under base mediated conditions.The transition-metal-free catalytic protocol provided high catalytic activity for direct C-H arylation reaction of unactivated arenes,and thus offered a convenient and efficient alternative for the construction biaryl scaffolds.In addition,the salen-porphyrin based CMP material possessed remarkable adsorption capability for the removal of organic amines from water.

Incorporation of carbazole and boron-containing dye into conjugated microporous polymers with significant aerobic oxidative photocatalysis

Carbazole-based conjugated microporous polymers(CMPs)as a new type of advanced porous material have created tremendous research curiosities in the area of photocatalysis.Besides,introducing boron-containing dyes into the CMPs framework was rare but will be rather promising due to their unique properties,including strong electron-accepting capability,efficient catalytic behaviour,significant absorption coefficient and high quantum.Herein,we rationally designed and prepared two new CMPs,i.e.Cz-BF_(2)-CMP and Cz-BPh2-CMP with the combination of carbazole and boron-containing dye as electron donor and acceptor motifs,respectively.Due to the efficient D-A effect between carbazole and boron-dye which not only accelerated the interfacial charge transfer efficiency but also improved the separation capability of photogenerated electron-hole pairs,both CMPs exhibited excellent photocatalytic performances in organic transformations such as green synthesis of benzimidazole in aqueous solution and aerobic oxidation of thioether in EtOH.

A redox-active conjugated microporous polymer cathode for highperformance lithium/potassium-organic batteries

Organic redox-active materials have emerged as a class of electrode materials for rechargeable batteries due to their high redox activity,low cost,structure diversity and flexibility.However,the high solubility of organic small molecules in organic electrolytes commonly leads to the fast capacity decay with cycling.Herein,we report a redox-active conjugated microporous polymer of poly(pyrene-co-anthraquinone)(Py Aq)cathode material consisting of pyrene and anthraquinone units.Benefiting from the highly cross-linked polymer structure with insoluble nature in organic electrolytes,the high surface area and the plentiful redox-active carbonyl groups,the Py Aq cathode demonstrates outstanding electrochemical performances for both lithium-ion batteries(LIBs)and potassium-ion batteries(KIBs).Specifically,the Py Aq cathode for LIBs delivers a high reversible capacity of 169 m Ah g^-1 at the current density of 20 m A g^-1,a high rate capability(142 m Ah g^-1 at 1000 m A g^-1)and an excellent cycling stability for 4000 cycles.Additionally,the Py Aq cathode for KIBs also exhibits a high reversible capacity of143 m Ah g^-1 with a long cycling life over 800 cycles.The excellent electrochemical performance demonstrates that the newly developed Py Aq could be an attractive cathode material for the advanced energy storage technologies.

Sealing functional ionic liquids in conjugated microporous polymer membrane by solvent-assisted micropore tightening

Porous organic polymers hold great promise for molecular sieving membrane separation.Although the inclusion of functional ionic liquid(IL)in the pores offers a facile way to manipulate their separation properties,the IL leaching during the separation process is difficult to avoid.Herein,we report a strategy to in-situ encapsulate ILs into the micropores of the conjugated microporous polymer membrane via a 6-min electropolymerization and further seal the aperture of the pores to prevent ILs leaching by solvent-assisted micropore tightening(SAMT).Upon screening the binding energy between different ILs and gas molecules,two ILs were selected to be incorporated into the membrane for CO_(2)/CH_(4) and O_(2)/N_(2) gas separations.The resultant separation performances surpass the 2008 Robeson upper bound.Notably,the ILs can be locked in the micropores by a facile high surface tension solvent treatment process to improve their separation stability,as evidenced by a 7-day continuous test.This simple and controllable process not only enables efficient and steady separation performance but also provides an effective strategy for confining and sealing functional guest molecules in the porous solids for various applications.

In Situ Growth of Flexible Polyphenylene-Conjugated Microporous Polymer Films for Fluorescence Detection of the Total Quantity of Developing Agents and Their Oxidation Products

Conjugated microporous polymers(CMPs)are a kind of porous skeleton polymers,which are characterized by extended conjugated skeletons,large specific surface area and structure stability.In this work,a facile and versatile method was developed to fabricate flexible conjugated microporous polymer films for fast detecting the total quantity of developing agents and their oxidation products.Conjugated microporous polymer films were synthesized through in situ one-step approach by Suzuki coupling reaction.With such merits such as intense luminescence,easy synthesis and disposability,the polymer films were employed to detect developers based on fluorescence quenching in the printing wastewater.A linear response to p-benzoquinone,oxidation product of developers,was obtained in the range of 0.05-0.5 lmolL-1,with a detection limit of 0.015 lmolL-1.The strategy for in situ growth of flexible polyphenylene-conjugated microporous polymer(PP-CMP)films seems to be a very portable and general method for meeting different analytic purposes.

共轭微孔聚合物研究进展

共轭微孔聚合物(CMPs)有制作方法简单多样、比表面积大、物理化学稳定性好、结构形貌可调等特点,因此受到广泛关注。近年来,共轭微孔聚合物的多种合成方法和新应用成为了研究热点,CMPs主要用途包括超级电容器、非均相催化、化学传感器、太阳能界面蒸发、抑菌材料、阻燃材料。重点介绍了共轭微孔聚合物的多种合成方法以及CMPs的多种应用领域,并且对目前合成CMPs的难点进行总结。