ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Qikai Li,Qing Zhou,Wangping Xu,Long Wen,Jun Li,Biao Deng,Jiajia Zhang,Hu Xu,Weishu Liu
Poly(3,4-ethylene dioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) thermoelectric thin films have attracted significant interest due to their solution-processable manufacturing. However, molecular-level tuning or doping is still a challenge to synergistically boost their thermoelectric performance and mechanically stretchable capabilities. In this work, we report a counterion exchange between ionic liquid bis(x-fluorosulfonyl) amide lithium (Li:nFSI, n = 1, 3, 5) with different sizes of anions and a PEDOT:PSS-induced bipolaron network, which significantly boosted the thermoelectric power factor from 0.8 to 157 μW m K–2 at 235 °C and the maximum tensile strain from 3% to over 30%. The π–π* stacking of the PEDOT polymer chains was fine-tuned by the hydrophobic anions of nFSI–, providing a technical route for constructing a bipolaron network and inducing the transition from hopping transport to band-like transport. Furthermore, we found that the stretchable capabilities, that is, εmax, were connected to the gelation time of the PEDOT:PSS-Li:nFSI aqueous solution. Thus, more fluorine-containing groups resulted in longer gelation times and higher εmax values, which significantly improved the processability of the solution-derived films.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
PubMed
高影响因子
LANGMUIR
·
2019
·
IF 3.683
Hongtao Cai,Ran Kou,Guangming Liu
In this work, poly(sodium styrene sulfonate) brushes have been employed as a precursor to prepare thermosensitive strong polyelectrolyte brushes (SPBs) through a counterion exchange strategy. The substitution of hydrophilic Na+ counterions by hydrophobic tetraalkylphosphonium counterions leads to a thermoresponsivity of the SPBs. The thermosensitive properties including hydration, stiffness, and surface water wettability of the SPBs can be modulated by the type of the tetraalkylphosphonium counterions. Nevertheless, the wet thickness of the SPBs with tetraalkylphosphonium counterions does not exhibit an obvious temperature dependency due to the high steric barrier in the crowded environment of SPBs generated by the large tetraalkylphosphonium counterions. The mixtures of small Na+ counterions and large tetraalkylphosphonium counterions are employed to realize the thermosensitive wet thickness without sacrificing other thermoresponsive properties of the SPBs because the mixed counterions can bring both a certain hydrophobicity and some free space to the brushes. This work opens up the opportunities available for the use of counterions to tune the thermosensitivity of SPBs.
研究领域:
材料科学
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聚合物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 23
·12367-12376
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IF 7.443
Ying Tang,Beibei Tang,Peiyi Wu
In this work, we report a novel method to prepare a positively charged nanofiltration (NF) membrane by rapid counter-ion exchange of a poly(ionic liquid) (PIL) in aqueous solution, which transforms from being hydrophilic to hydrophobic. A thin PIL layer is deposited on the supporting membrane via a phase separation process induced by an ion exchange reaction along with a self-inhibiting effect, and a series of positively charged NF membranes are obtained. The membrane formation process is mainly dominated by the concentration of the hydrophilic PIL and its counter-ions. In brief, the density of the top layer is predominated both by the PIL and its aqueous counter-ion, and the thickness of the surface layer is mainly determined by the aqueous counter-ion. A streaming potential measurement confirmed that the resultant membrane is positively charged when the pH range is below 11. The pure water flux (PWF) was up to 45.3 L m−2 h−1 under the operating pressure of 0.6 MPa. The rejection to MgCl2 of the membrane reached 84% and decreased in the order of MgCl2, NaCl, MgSO4, and Na2SO4. It also shows a high rejection of about 90% to heavy metallic salts such as CuCl2, NiCl2 and CoCl2. The method based on the hydrophilic–hydrophobic transformation of the PIL provides an alternative way to prepare a charged membrane with high performance.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Guangyu Zhang,Xin Zhang,Meng Li,Zhaohui Su
A strategy combining polyelectrolyte multilayer (PEM) deposition and counterion exchange was developed to fabricate wettability gradient surfaces on rough aluminum with wetting characters continuously varied from superoleophilic to superoleophobic. Counterion exchange kinetics was adopted as a means to tailor the surface chemical composition spatially, with the gradient ultimately reflecting position-dependent immersion time during the dipping of substrate in salt solution. Wettability depended on the identity and concentration of the counterion in the outermost PEM layer. Gradients could be erased and rewritten through the exchange of counterions, and the gradient’s wetting character was evaluated by measuring both water and oil contact angles. The surface chemical composition gradient was further investigated by X-ray photoelectron spectroscopy.
研究领域:
材料科学
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表面化学
✓ 已验证
DOI
高影响因子
CHINESE SCIENCE BULLETIN
·
2010
·Vol. 55
·期 31
·3562-3568
·
IF 0.917
Yang Wu,He XiaoJing,Gao JinZhang,Guo Hao,He XiaoYan,Wan Fei,Zhao XiuLi,Yu Yan,Pei Ben
Well-defined poly (ionic liquid) brushes with tunable wettability are successfully synthesized via nitroxide-mediated radical polymerization. X-ray photoelectron spectroscopy, attenuated total reflection infrared spectroscopy and static water contact angle measurements are used to monitor each step. Ellipsometry, nuclear magnetic resonance ( 1 H and 13 C) spectra and gel permeation chromatographic measurements reveal that there is a linear increase in polymer film thickness with polymerization time, indicating that chain growth from the surface is a controlled/“living” polymerization. The surface morphology was measured by atomic force microscopy. Moreover, the surfaces of the poly (ionic liquid) brushes with tunable wettability and reversible switching between hydrophilicity and hydrophobicity can be easily achieved by counteranion exchange.
研究领域:
材料科学
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高分子化学
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表面科学
✓ 已验证
DOI
高影响因子
ChemPlusChem
·
2023
·
IF 3.4
Aries Kwok-Heung Chan,Ming-Hin Chau,Yikun Ren,Jia-Jun Jiang,Man-Kin Wong,Franco King-Chi Leung
Graphical The first chiral gold (III) amphiphile enables chiral supramolecular assembly in aqueous media, confirmed by circular dichroic and electron microscopy, with potential supramolecular helicity enhancement controlled by packing parameters of the amphiphilic design. The resulting chiral supramolecular assembly shows good cytocompatibility. Gold (III) cyclometalated based amphiphiles in aqueous media have been revealed with excellent supramolecular transformations to external stimuli to open new pathways for soft functional material fabrications. Herein, we report a new chiral cyclometalated gold (III) amphiphile ( GA) assembling into lamellar nanostructures in aqueous media confirmed with transmission electron microscopy (TEM). Counterion exchange with D -, L -, or racemic-camphorsulfonates features the significant supramolecular helicity enhancements, enabling transformations of GA from lamellar structure to vesicles and to nanotubes with multi-equivalents of counterion. The limited cytotoxicity of GA in aqueous media exhibits good biocompatibility.
研究领域:
超分子化学
·
材料科学
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纳米技术
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生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）