Here, we report an observation that illustrate the potential of polyelectrolyte microgels in salt-free solutions to display a high ionic conductivity. Laser light scattering and ionic conductivity tests on very dilute...Here, we report an observation that illustrate the potential of polyelectrolyte microgels in salt-free solutions to display a high ionic conductivity. Laser light scattering and ionic conductivity tests on very dilute aqueous dispersions of the microgels indicate that both small size and swollen state of gel particles play vital roles, which should favor the counterions to freely penetrate and leave gel particles, and thus can contribute to the ion-conducting property. Upon discovering this on microgels that are composed of imidazolium-based poly(ionic liquid), we also illustrate the generality of the finding to single lithium-ion polyelectrolyte microgels that are of more technically relevant features for applications, for instance, as injectable liquid “microgel-in-solution” electrolytes of high conductivity(ca. 8.2 × 10^(-2)S/m at 25.0 ℃ for1.0 × 10^(-2)g/m L of microgels in a LiNO_(3)-free 1:1 v/v mixture of 1,2-dioxolane and dimethoxymethane) and high lithium-ion transference number(0.87) for use in the rechargeable lithium-sulfur battery.展开更多
Electrochromic devices(ECDs)have exhibited promising applications in the fields of energy-saving intelligent buildings and next-generation displays because of their simple structure,low power consumption,and multicolo...Electrochromic devices(ECDs)have exhibited promising applications in the fields of energy-saving intelligent buildings and next-generation displays because of their simple structure,low power consumption,and multicolor displays.W_(18)O_(49)/polyaniline(PANI)hybrid films are prepared and assembled to ECDs.Compared with pure PANI and W_(18)O_(49) films,the hybrid film exhibits superior electrochemical and electrochromic performance,including high optical modulation(70.2%),large areal capacity(79.6 mF/cm^(2)),and good capacitance retention.The excellent electrochemical and electrochromic performance is ascribed to the formation of the donor(PANI)-acceptor(W_(18)O_(49))pair,the porous structure in the nanowires,and the large surface area,which enhance electron delocalization of the W_(18)O_(49)/PANI,improve the ion diffusion rate,and increase the charge storage sites.Furthermore,benefitting from the outstanding optical,electrical,and multifunctional properties,the W_(18)O_(49)/PANI hybrid film-based ECD platform is expected to play an important role in electrochromism and energy storage.展开更多
Here, we report a finding on light-mediated CO_(2)^(-)responsiveness. It is found on the microgels that are made of side-chain type metallopolymers containing metalla-aromatics. Turbidity and laser light scattering st...Here, we report a finding on light-mediated CO_(2)^(-)responsiveness. It is found on the microgels that are made of side-chain type metallopolymers containing metalla-aromatics. Turbidity and laser light scattering studies on dilute aqueous dispersion of these microgels in dark indicate high CO_(2)^(-)responsivity, but poor reversibility upon N2 purge, which can be improved by exposing to light. This light-mediated CO_(2)^(-)responsiveness can be elucidated by the loss of aromaticity from initial photoexcitation and concurrent formation of a less reactive, antiaromatic excited state of relatively low CO_(2) binding affinity, and by subsequent relief of antiaromaticity that can enhance the CO_(2) removal. The finding is also checked by CO_(2) uptake-release experiments on the microgels, which enables both CO_(2) capture of high capacity and CO_(2) removal of good reversibility under a mild condition, allowing effective and reversible response to dilute CO_(2).展开更多
Silver nanoparticles with average diameter of 10 ± 3 nm were synthesized within the sieves of poly(N-isopropylacrylamide-2-hydroxyethylmethacrylate-acrylic acid)(p(NIPAAm-HEMA-AAc))polymer microgels. Free r...Silver nanoparticles with average diameter of 10 ± 3 nm were synthesized within the sieves of poly(N-isopropylacrylamide-2-hydroxyethylmethacrylate-acrylic acid)(p(NIPAAm-HEMA-AAc))polymer microgels. Free radial emulsion polymerization was employed for synthesis of p(NIPAAm-HEMA-AAc) polymer microgels. Silver nanoparticles were introduced within the microgels sphere by in situ reduction method. Microgels and hybrid microgels were characterized by Fourier transform infrared spectroscopy, ultra violet-visible spectroscopy,transmission electron microscopy and dynamic light scattering measurements. Catalytic activity of Ag-p(NIPAAm-HEMA-AAc) hybrid microgels was studied using catalytic reduction of 4-nitrophenol(4-NP) as a model reaction in aqueous media. The influence of sodium borohydride(Na BH4) concentration, catalyst dose and 4-NP concentration on catalytic reduction of 4-NP was investigated. A linear relationship was found between catalyst dose and apparent rate constant(kapp). The mechanism of catalysis by hybrid microgels was explored for further development in this area. The deep analysis of catalytic process reveals that the unique combination of NIPAAm, HEMA and AAc does not only stabilize silver nanoparticles in polymer network but it also enhances the mass transport of hydrophilic substrate like 4-NP from outside to inside the polymer network.展开更多
基金supported by National Natural Science Foundation of China (Nos.21774105 and 20923004)Chuying Plan Youth Topnotch Talents of Fujian Province,National Fund for Fostering Talents of Basic Science (No.J1310024)。
文摘Here, we report an observation that illustrate the potential of polyelectrolyte microgels in salt-free solutions to display a high ionic conductivity. Laser light scattering and ionic conductivity tests on very dilute aqueous dispersions of the microgels indicate that both small size and swollen state of gel particles play vital roles, which should favor the counterions to freely penetrate and leave gel particles, and thus can contribute to the ion-conducting property. Upon discovering this on microgels that are composed of imidazolium-based poly(ionic liquid), we also illustrate the generality of the finding to single lithium-ion polyelectrolyte microgels that are of more technically relevant features for applications, for instance, as injectable liquid “microgel-in-solution” electrolytes of high conductivity(ca. 8.2 × 10^(-2)S/m at 25.0 ℃ for1.0 × 10^(-2)g/m L of microgels in a LiNO_(3)-free 1:1 v/v mixture of 1,2-dioxolane and dimethoxymethane) and high lithium-ion transference number(0.87) for use in the rechargeable lithium-sulfur battery.
基金supported by the National Natural Scientific Foundation of China(No.21804074)China Postdoctoral Science Foundation(No.2020T130331)the Open Funds of the State Key Laboratory of Physical Chemistry of Solid Surfaces(No.202023).
文摘Electrochromic devices(ECDs)have exhibited promising applications in the fields of energy-saving intelligent buildings and next-generation displays because of their simple structure,low power consumption,and multicolor displays.W_(18)O_(49)/polyaniline(PANI)hybrid films are prepared and assembled to ECDs.Compared with pure PANI and W_(18)O_(49) films,the hybrid film exhibits superior electrochemical and electrochromic performance,including high optical modulation(70.2%),large areal capacity(79.6 mF/cm^(2)),and good capacitance retention.The excellent electrochemical and electrochromic performance is ascribed to the formation of the donor(PANI)-acceptor(W_(18)O_(49))pair,the porous structure in the nanowires,and the large surface area,which enhance electron delocalization of the W_(18)O_(49)/PANI,improve the ion diffusion rate,and increase the charge storage sites.Furthermore,benefitting from the outstanding optical,electrical,and multifunctional properties,the W_(18)O_(49)/PANI hybrid film-based ECD platform is expected to play an important role in electrochromism and energy storage.
基金supported by National Natural Science Foundation of China (Nos. 21774105, 21805164, 20923004)Chuying Plan Youth Top-notch Talents of Fujian ProvinceNational Fund for Fostering Talents of Basic Science (No. J1310024)。
文摘Here, we report a finding on light-mediated CO_(2)^(-)responsiveness. It is found on the microgels that are made of side-chain type metallopolymers containing metalla-aromatics. Turbidity and laser light scattering studies on dilute aqueous dispersion of these microgels in dark indicate high CO_(2)^(-)responsivity, but poor reversibility upon N2 purge, which can be improved by exposing to light. This light-mediated CO_(2)^(-)responsiveness can be elucidated by the loss of aromaticity from initial photoexcitation and concurrent formation of a less reactive, antiaromatic excited state of relatively low CO_(2) binding affinity, and by subsequent relief of antiaromaticity that can enhance the CO_(2) removal. The finding is also checked by CO_(2) uptake-release experiments on the microgels, which enables both CO_(2) capture of high capacity and CO_(2) removal of good reversibility under a mild condition, allowing effective and reversible response to dilute CO_(2).
基金financial support for research from Higher Education Commission Pakistan under National Research Program for Universities(NRPU)(No.20-3995/WRPU/R&D/HEC/14/1212)Research Centre for Advanced Materials Science - King Khalid University, Saudi Arabia for support
文摘Silver nanoparticles with average diameter of 10 ± 3 nm were synthesized within the sieves of poly(N-isopropylacrylamide-2-hydroxyethylmethacrylate-acrylic acid)(p(NIPAAm-HEMA-AAc))polymer microgels. Free radial emulsion polymerization was employed for synthesis of p(NIPAAm-HEMA-AAc) polymer microgels. Silver nanoparticles were introduced within the microgels sphere by in situ reduction method. Microgels and hybrid microgels were characterized by Fourier transform infrared spectroscopy, ultra violet-visible spectroscopy,transmission electron microscopy and dynamic light scattering measurements. Catalytic activity of Ag-p(NIPAAm-HEMA-AAc) hybrid microgels was studied using catalytic reduction of 4-nitrophenol(4-NP) as a model reaction in aqueous media. The influence of sodium borohydride(Na BH4) concentration, catalyst dose and 4-NP concentration on catalytic reduction of 4-NP was investigated. A linear relationship was found between catalyst dose and apparent rate constant(kapp). The mechanism of catalysis by hybrid microgels was explored for further development in this area. The deep analysis of catalytic process reveals that the unique combination of NIPAAm, HEMA and AAc does not only stabilize silver nanoparticles in polymer network but it also enhances the mass transport of hydrophilic substrate like 4-NP from outside to inside the polymer network.