| 1. |
- Alkarmo, Walid, et al.
(författare)
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Poly(ionic liquid)-Derived N-Doped Carbons with Hierarchical Porosity for Lithium- and Sodium-Ion Batteries
- 2019
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Ingår i: Macromolecular rapid communications. - : Wiley. - 1022-1336 .- 1521-3927. ; 40:1
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Tidskriftsartikel (refereegranskat)abstract
- The performance of lithium- and sodium-ion batteries relies notably on the accessibility to carbon electrodes of controllable porous structure and chemical composition. This work reports a facile synthesis of well-defined N-doped porous carbons (NPCs) using a poly(ionic liquid) (PIL) as precursor, and graphene oxide (GO)-stabilized poly(methyl methacrylate) (PMMA) nanoparticles as sacrificial template. The GO-stabilized PMMA nanoparticles are first prepared and then decorated by a thin PIL coating before carbonization. The resulting NPCs reach a satisfactory specific surface area of up to 561 m(2) g(-1) and a hierarchically meso- and macroporous structure while keeping a nitrogen content of 2.6wt%. Such NPCs deliver a high reversible charge/discharge capacity of 1013 mA h g(-1) over 200 cycles at 0.4A g(-1) for lithium-ion batteries, and show a good capacity of 204 mAh g(-1) over 100 cycles at 0.1A g(-1) for sodium-ion batteries.
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| 2. |
- Jiang, Zhiping, et al.
(författare)
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Fine tuning the hydrophobicity of counter-anions to tailor pore size in porous all-poly(ionic liquid) membranes
- 2019
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Ingår i: Polymer international. - : Wiley. - 0959-8103 .- 1097-0126. ; 68:9, s. 1566-1569
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Tidskriftsartikel (refereegranskat)abstract
- Charged porous polymer membranes (CPMs) emerging as a multifunctional platform for diverse applications in chemistry, materials science and biomedicine have been attracting widespread attention. Fabrication of CPMs in a controllable manner is of particular significance for optimizing their function and maximizing practical values. Herein, we report the fabrication of CPMs exclusively from poly(ionic liquid)s (PILs), and their pore size and wettability were precisely tailored by rational choice of counter-anions. Specifically, a stepwise subtle increase in hydrophobicity of the counter-anions by extending the length of fluorinated alkyl substituents, i.e. from bis(trifluoromethane sulfonyl)imide to bis(pentafluoroethane sulfonyl)imide and bis(heptafluoropropane sulfonyl)imide, decreased the average pore size gradually from 1546 to 157 and 77 nm, respectively. Meanwhile, the corresponding water contact angles increased from 90 degrees to 102 degrees and 120 degrees. The sensitive control over the porous architectures and surface wettability of CPMs by systematic variation of anion hydrophobicity provides solid proof of the impact of PIL anions on CPM structure.
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| 3. |
- Khorsand Kheirabad, Atefeh, 1991-, et al.
(författare)
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Porous Poly(ionic liquid) Membranes and Ionic Organic Cages
- 2019
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Konferensbidrag (refereegranskat)abstract
- This poster will present two topics that are active in our research group, the porous poly(ionic liquid) membranes and the ionic organic cages.Functional nanoporous polymer membranes with expanded surface area can be applied in broad fields, including separation, filtration, catalysis and energy applications. There are a number of established methods for the preparation of nanoporous membranes using neutral or weakly charged polymers. Although, fabrication of nanoporous polymer membranes from strong polyelectrolytes is far more difficult, we present our approach to nanoporous polyelectrolyte membranes by using poly(ionic liquid)s. [1] Poly(ionic liquid)s (PILs) are the polymerization products of ionic liquids, which combine certain properties and functions of polymeric materials (e,g. durability and good processability) and ILs (e.g. ion conductivity and thermal stability). We have exploited these favorable properties in the fabrication of nanoporous membranes from imidazolium based PILs through electrostatic complexation of PILs with polyacids. [2,3] The porous structure forms as a result of microphase separation of the hydrophobic PIL chains from the aqueous environment and is simultaneously stabilized by ionically crosslinked networks between the cationic PIL and the negatively charged neutralized polyacids. The membrane pore sizes can be tuned from nano- to micrometer scale by varying the degree of electrostatic complexation. In this meeting, we will update you with our latest progress in making nanoparticle-decorated nanoporous PIL membranes in a single step.In the ionic organic cage part, we present our work about operating ionic organic cages (I-cages) to enclose small noble metal clusters (MCs) with adaptivity to water-oil phase. Organic molecular cages are a kind of multifunctional materials with molecular solubility, intrinsic open channels and unique ability to accommodate guest objects such as (MCs). [4] Herein, we report physical confinement of small noble MCs inside I-cages. [5] Metal clusters (MCs) are small sized particles < 2nm with significant properties such as discrete electronic structures, intense photoluminescence, high catalytic activity (hydrogeneration, oxidation, and coupling reactions). Dominated synthesis methods of MCs includes the surface-binding ligand approach (amphiphilic capping agents, and water-oil phase transfer agents). [6]
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| 4. |
- Khorsand Kheirabad, Atefeh, 1991-, et al.
(författare)
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Porous Poly(ionic liquid) Membranes Functionalized with Metal Nanoparticles
- 2019
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Konferensbidrag (refereegranskat)abstract
- Functional nanoporous polymer membranes with expanded surface area can be applied in broad fields, including separation, filtration, catalysis and energy applications. There are a number of established methods for the preparation of nanoporous membranes using neutral or weakly charged polymers. Although, fabrication of nanoporous polymer membranes from strong polyelectrolytes is far more difficult, we present our approach to nanoporous polyelectrolyte membranes by using poly(ionic liquid)s. [1]Poly(ionic liquid)s (PILs) are the polymerization products of ionic liquids (ILs), which combine certain properties and functions of polymeric materials (e,g. durability and good processability) and ILs (e.g. ion conductivity and thermal stability). We have exploited these favorable properties in the fabrication of nanoporous membranes from imidazolium based PILs through electrostatic complexation of PILs with polyacids. [2-4] The porous structure forms as a result of microphase separation of the hydrophobic PIL chains from the aqueous environment and is simultaneously stabilized by ionically crosslinked networks between the cationic PIL and the negatively charged neutralized polyacids. The as-obtained nanoporous membrane features a gradient profile in the cross-linking density along the membrane cross-section, triggered by the diffusive penetration of a base molecule from the top to the bottom into the PIL-polyacid blend film. The membrane pore sizes can be tuned from nano- to micrometer scale by varying the degree of electrostatic complexation.Furthermore, the membrane features high actuation speed in response to acetone vapor phase (also some other organic vapors) on account of its gradient in cross-linking density and the intrinsic porous nature of the membrane that enhances the internal mass transport. Such membranes may serve as environmental sensors to detect solvent quality. [5] In this meeting, we will update you with our latest progress in making nanoparticle-decorated nanoporous PIL membranes in a single step.
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| 5. |
- Lin, Huijuan, et al.
(författare)
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Organic Molecule-Driven Polymeric Actuators
- 2019
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Ingår i: Macromolecular rapid communications. - : Wiley. - 1022-1336 .- 1521-3927. ; 40:7
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Forskningsöversikt (refereegranskat)abstract
- Inspired by the motions of plant tissues in response to external stimuli, significant attention has been devoted to the development of actuating polymeric materials. In particular, polymeric actuators driven by organic molecules have been designed due to their combined superiorities of tunable functional monomers, designable chemical structures, and variable structural anisotropy. Here, the recent progress is summarized in terms of material synthesis, structure design, polymer-solvent interaction, and actuating performance. In addition, various possibilities for practical applications, including the ability to sense chemical vapors and solvent isomers, and future directions to satisfy the requirement of sensing and smart systems are also highlighted.
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| 6. |
- Sigolaeva, Larisa, et al.
(författare)
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Long-term stable poly(ionic liquid)/MWCNTs inks enable enhanced surface modification for electrooxidative detection and quantification of dsDNA
- 2019
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Ingår i: Polymer. - : Elsevier BV. - 0032-3861 .- 1873-2291. ; 168, s. 95-103
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Tidskriftsartikel (refereegranskat)abstract
- This work demonstrates the use of imidazolium-based poly(ionic liquid)s (PILs) as efficient dispersants of multiwalled carbon nanotubes (MWCNTs). With these polymeric dispersants, highly stable fine dispersions of MWCNTs (inks) can be easily prepared in aqueous media and applied for rather simple but efficient surface modification of screen-printed electrodes (SPEs). Such a modification of SPEs remarkably increases the electroactive surface area and accelerates the electron transfer rate due to synergistic combination of specific features of MWCNTs such as strong adsorptive property and high specific surface with the advantages of PILs like ion conductivity and dispersability. We further show that the PIL/MWCNT-modified SPEs can be beneficially utilized for direct electrochemical analysis of double stranded DNA (dsDNA). Specifically, it is exemplified by the direct electrooxidation of guanine and adenine bases in salmon testes dsDNA chosen as a model system. The linear ranges for the determination of dsDNA correspond to 5-500 mu g/mL for the oxidative peak of guanine and 0.5-50 mu g/mL for the oxidative peak of adenine. This makes direct electrochemical dsDNA detection with the use of the easy-preparable PIL/MWCNT-modified SPEs strongly competing to currently applied spectral and fluorescent techniques. Furthermore, we show that the developed constructs are capable of sensing a single point mutation in the 12-bases single-stranded DNA fragments. Such detection is of high clinical significance in choosing an adequate anticancer treatment, where the electrochemical identification of the point mutation could offer time and cost benefits.
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| 7. |
- Tang, Qingquan, et al.
(författare)
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Templated synthesis of cyclic poly(ionic liquid)s
- 2019
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Ingår i: Reactive & functional polymers. - : Elsevier BV. - 1381-5148 .- 1873-166X. ; 138, s. 1-8
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Tidskriftsartikel (refereegranskat)abstract
- Charged cyclic polymers, e.g. cyclic DNAs and polypeptides, play enabling roles in organisms, but their synthesis was challenging due to the well-known polyelectrolyte effect. To tackle the challenge, we developed a templated method to synthesize a library of imidazolium and pyridinium based cyclic poly(ionic liquid)s. Cyclic templates, cyclic polyimidazole and poly(2-pyridine), were synthesized first through ring-closure method by light-induced Diels - Alder click reaction. Through quaternization of cyclic templates followed by anion metathesis, the cyclic poly(ionic liquid)s were synthesized, which paired with varied counter anions.
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| 8. |
- Wang, Tongzhou, et al.
(författare)
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Atomically Dispersed Semi-Metallic Selenium on Porous Carbon Membrane as an Electrode for Hydrazine Fuel Cells
- 2019
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Ingår i: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 58:38, s. 13466-13471
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Tidskriftsartikel (refereegranskat)abstract
- Electrochemically functional porous membranes of low cost are appealing in various electrochemical devices used in modern environmental and energy technologies. Herein we describe a scalable strategy to construct electrochemically active, hierarchically porous carbon membranes containing atomically dispersed semi-metallic Se, denoted SeNCM. The isolated Se atoms were stabilized by carbon atoms in the form of a hexatomic ring structure, in which the Se atoms were located at the edges of graphitic domains in SeNCM. This configuration is different from that of previously reported transition/noble metal single atom catalysts. The positively charged Se, enlarged graphitic layers, robust electrochemical nature of SeNCM endow them with excellent catalytic activity that is superior to state-of-the-art commercial Pt/C catalyst. It also has long-term operational stability for hydrazine oxidation reaction in practical hydrazine fuel cell.
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| 9. |
- Yahia, Mohamed, et al.
(författare)
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Linear Main-Chain 1,2,4-Triazolium Poly(ionic liquid)s : Single-Step Synthesis and Stabilization of Cellulose Nanocrystals
- 2019
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Ingår i: ACS Macro Letters. - : American Chemical Society (ACS). - 2161-1653. ; 8:10, s. 1372-1377
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Tidskriftsartikel (refereegranskat)abstract
- Linear main-chain 1,2,4-triazolium-based poly(ionic liquid)s (PILs) were synthesized in this contribution. The polymerization process is experimentally very simple and involves only a single-step polycondensation of a commercially available monomer in DMSO as solvent at 120 degrees C. Their thermal stability and solubility were analyzed in terms of different counteranions. Due to the ease of this synthetic route, it was readily applied to graft onto sulfonated cellulose nanocrystals (CNCs) via a one-step in situ polymerization. The as synthesized PIL@CNC hybrid colloids exhibit adaptive dispensability in water and organic solvents.
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| 10. |
- Zhang, Su-Yun, et al.
(författare)
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Ionic organic cage-encapsulating phase-transferable metal clusters
- 2019
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Ingår i: Chemical Science. - : Royal Society of Chemistry (RSC). - 2041-6520 .- 2041-6539. ; 10:5, s. 1450-1456
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Tidskriftsartikel (refereegranskat)abstract
- Exploration of metal clusters (MCs) adaptive to both aqueous and oil phases without disturbing their size is promising for a broad scope of applications. The state-of-the-art approach via ligandbinding may perturb MCs' size due to varied metal-ligand binding strength when shuttling between solvents of different polarity. Herein, we applied physical confinement of a series of small noble MCs (<1 nm) inside ionic organic cages (I-Cages), which by means of anion exchange enables reversible transfer of MCs between aqueous and hydrophobic solutions without varying their ultrasmall size. Moreover, the MCs@I-Cage hybrid serves as a recyclable, reaction-switchable catalyst featuring high activity in liquid-phase NH3BH3 (AB) hydrolysis reaction with a turnover frequency (TOF) of 115 min(-1).
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