The Experts below are selected from a list of 93 Experts worldwide ranked by ideXlab platform
Qingshan Kong - One of the best experts on this subject based on the ideXlab platform.
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cellulose polysulfonamide composite membrane as a high performance lithium ion battery separator
ACS Sustainable Chemistry & Engineering, 2014Co-Authors: Qingshan Kong, Jianjun Zhang, Liping Yue, Zhihong Liu, X P Wang, Rongzhan Liu, Yulong Duan, Guanglei CuiAbstract:Battery separators have drawn considerable attention due to their vital roles for the safety and electrochemical performance of lithium-ion batteries. In this paper, the cellulose/polysulfonamide composite membrane was successfully fabricated from a mixture of microfibrillar cellulose and polysulfonamide via a facile papermaking process. And its potential application was explored as a high performance lithium-ion battery separator by characterizing their electrolyte wettability, heat tolerance, and electrochemical properties. Lithium cobalt oxide/graphite cells using the separator displayed better capacity retention ratios of 85% after 100 cycles and superior rate capability compared with those of a commercial polypropylene separator. Furthermore, the lithium iron phosphate/lithium half cell using cellulose/polysulfonamide separator exhibited stable charge–discharge capability even at 120 °C. It was demonstrated that the composite separator possessed an enhanced thermal dimensional stability. This researc...
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A Heat-Resistant Silica Nanoparticle Enhanced Polysulfonamide Nonwoven Separator for High-Performance Lithium Ion Battery
Journal of The Electrochemical Society, 2013Co-Authors: Jianjun Zhang, Xinhong Zhou, Qingshan Kong, Liping Yue, Zhihong Liu, Chuanjian Zhang, Shuping Pang, Xuejiang Wang, Jianhua Yao, Guanglei CuiAbstract:In this paper, a heat-resistant silica nanoparticle enhanced polysulfonamide nonwoven separator has been successfully explored by electrospinning method followed by a dip-coating process for high-performance lithium ion battery. In comparison to Celgard 2500 separator, silica nanoparticle enhanced polysulfonamide nonwoven separator possessed higher porosity, better electrolyte uptake, superior thermal resistance and higher ionic conductivity. The lithium cobalt oxide (LiCoO2)/graphite cell using silica nanoparticle enhanced polysulfonamide nonwoven separator displayed better rate capability and superior capacity retention than that of Celgard 2500 separator. Moreover, silica nanoparticle enhanced polysulfonamide nonwoven separator based lithium iron phosphate (LiFePO4)/lithium(Li) cell exhibited stable charge-discharge capability and satisfactory cycle performance even at a high temperature of 120 degrees C. These advanced characteristics would boost the application of silica nanoparticle enhanced polysulfonamide nonwoven separator for high-power lithium ion battery. (C) 2013 The Electrochemical Society. All rights reserved.
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a core shell structured polysulfonamide based composite nonwoven towards high power lithium ion battery separator
Journal of The Electrochemical Society, 2013Co-Authors: Xinhong Zhou, Jianjun Zhang, Qingshan KongAbstract:A core-shell structured polysulfonamide@polyvinylidene fluoride-co-hexafluoropropene composite nonwoven separator was exploited for lithium ion battery via coaxial electrospinning technique for enhanced safety characteristic of battery. Polysulfonamide (PSA) and polyvinylidene fluoride-co-hexafluoropropene (PVDF-HFP) were used as the inner (core) and outer (shell) layer, respectively. Compared with the commercial polypropylene (PP) separator, the PSA@PVDF-HFP composite nonwoven separator manifested higher porosity, better electrolyte wettability and superior thermal stability. Moreover, it was demonstrated that the assembled cell with PSA@PVDF-HFP composite nonwoven separator displayed superior rate capability and better cycling capacity retention than those of PP separator. Notably, these attractive characteristics would endow PSA@PVDF-HFP composite nonwoven a promising separator for high power lithium ion battery. (C) 2013 The Electrochemical Society.
Guanglei Cui - One of the best experts on this subject based on the ideXlab platform.
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cellulose polysulfonamide composite membrane as a high performance lithium ion battery separator
ACS Sustainable Chemistry & Engineering, 2014Co-Authors: Qingshan Kong, Jianjun Zhang, Liping Yue, Zhihong Liu, X P Wang, Rongzhan Liu, Yulong Duan, Guanglei CuiAbstract:Battery separators have drawn considerable attention due to their vital roles for the safety and electrochemical performance of lithium-ion batteries. In this paper, the cellulose/polysulfonamide composite membrane was successfully fabricated from a mixture of microfibrillar cellulose and polysulfonamide via a facile papermaking process. And its potential application was explored as a high performance lithium-ion battery separator by characterizing their electrolyte wettability, heat tolerance, and electrochemical properties. Lithium cobalt oxide/graphite cells using the separator displayed better capacity retention ratios of 85% after 100 cycles and superior rate capability compared with those of a commercial polypropylene separator. Furthermore, the lithium iron phosphate/lithium half cell using cellulose/polysulfonamide separator exhibited stable charge–discharge capability even at 120 °C. It was demonstrated that the composite separator possessed an enhanced thermal dimensional stability. This researc...
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A Heat-Resistant Silica Nanoparticle Enhanced Polysulfonamide Nonwoven Separator for High-Performance Lithium Ion Battery
Journal of The Electrochemical Society, 2013Co-Authors: Jianjun Zhang, Xinhong Zhou, Qingshan Kong, Liping Yue, Zhihong Liu, Chuanjian Zhang, Shuping Pang, Xuejiang Wang, Jianhua Yao, Guanglei CuiAbstract:In this paper, a heat-resistant silica nanoparticle enhanced polysulfonamide nonwoven separator has been successfully explored by electrospinning method followed by a dip-coating process for high-performance lithium ion battery. In comparison to Celgard 2500 separator, silica nanoparticle enhanced polysulfonamide nonwoven separator possessed higher porosity, better electrolyte uptake, superior thermal resistance and higher ionic conductivity. The lithium cobalt oxide (LiCoO2)/graphite cell using silica nanoparticle enhanced polysulfonamide nonwoven separator displayed better rate capability and superior capacity retention than that of Celgard 2500 separator. Moreover, silica nanoparticle enhanced polysulfonamide nonwoven separator based lithium iron phosphate (LiFePO4)/lithium(Li) cell exhibited stable charge-discharge capability and satisfactory cycle performance even at a high temperature of 120 degrees C. These advanced characteristics would boost the application of silica nanoparticle enhanced polysulfonamide nonwoven separator for high-power lithium ion battery. (C) 2013 The Electrochemical Society. All rights reserved.
Jianjun Zhang - One of the best experts on this subject based on the ideXlab platform.
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a phase inversion based sponge like polysulfonamide sio2 composite separator for high performance lithium ion batteries
Chinese Journal of Chemical Engineering, 2018Co-Authors: Xiao Wang, Gaojie Xu, Qingfu Wang, Chenglong Lu, Chengzhong Zong, Jianjun ZhangAbstract:Abstract In this work, a sponge-like polysulfonamide (PSA)/SiO 2 composite membrane is unprecedentedly prepared by the phase inversion method, and successfully demonstrated as a novel separator of lithium-ion batteries (LIBs). Compared to the commercial polypropylene (PP) separator, the sponge-like PSA/SiO 2 composite possesses better physical and electrochemical properties, such as higher porosity, ionic conductivity, thermal stability and flame retarding ability. The LiCoO 2 /Li half-cells using the sponge-like composite separator demonstrate superior rate capability and cyclability over those using the commercial PP separator. Moreover, the sponge-like composite separator can ensure the normal operation of LiCoO 2 /Li half-cell at an extremely high temperature of 90 °C, while the commercial PP separator cannot. All these encouraging results suggest that this phase inversion based sponge-like PSA/SiO 2 composite separator is really a promising separator for high performance LIBs.
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cellulose polysulfonamide composite membrane as a high performance lithium ion battery separator
ACS Sustainable Chemistry & Engineering, 2014Co-Authors: Qingshan Kong, Jianjun Zhang, Liping Yue, Zhihong Liu, X P Wang, Rongzhan Liu, Yulong Duan, Guanglei CuiAbstract:Battery separators have drawn considerable attention due to their vital roles for the safety and electrochemical performance of lithium-ion batteries. In this paper, the cellulose/polysulfonamide composite membrane was successfully fabricated from a mixture of microfibrillar cellulose and polysulfonamide via a facile papermaking process. And its potential application was explored as a high performance lithium-ion battery separator by characterizing their electrolyte wettability, heat tolerance, and electrochemical properties. Lithium cobalt oxide/graphite cells using the separator displayed better capacity retention ratios of 85% after 100 cycles and superior rate capability compared with those of a commercial polypropylene separator. Furthermore, the lithium iron phosphate/lithium half cell using cellulose/polysulfonamide separator exhibited stable charge–discharge capability even at 120 °C. It was demonstrated that the composite separator possessed an enhanced thermal dimensional stability. This researc...
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A Heat-Resistant Silica Nanoparticle Enhanced Polysulfonamide Nonwoven Separator for High-Performance Lithium Ion Battery
Journal of The Electrochemical Society, 2013Co-Authors: Jianjun Zhang, Xinhong Zhou, Qingshan Kong, Liping Yue, Zhihong Liu, Chuanjian Zhang, Shuping Pang, Xuejiang Wang, Jianhua Yao, Guanglei CuiAbstract:In this paper, a heat-resistant silica nanoparticle enhanced polysulfonamide nonwoven separator has been successfully explored by electrospinning method followed by a dip-coating process for high-performance lithium ion battery. In comparison to Celgard 2500 separator, silica nanoparticle enhanced polysulfonamide nonwoven separator possessed higher porosity, better electrolyte uptake, superior thermal resistance and higher ionic conductivity. The lithium cobalt oxide (LiCoO2)/graphite cell using silica nanoparticle enhanced polysulfonamide nonwoven separator displayed better rate capability and superior capacity retention than that of Celgard 2500 separator. Moreover, silica nanoparticle enhanced polysulfonamide nonwoven separator based lithium iron phosphate (LiFePO4)/lithium(Li) cell exhibited stable charge-discharge capability and satisfactory cycle performance even at a high temperature of 120 degrees C. These advanced characteristics would boost the application of silica nanoparticle enhanced polysulfonamide nonwoven separator for high-power lithium ion battery. (C) 2013 The Electrochemical Society. All rights reserved.
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a core shell structured polysulfonamide based composite nonwoven towards high power lithium ion battery separator
Journal of The Electrochemical Society, 2013Co-Authors: Xinhong Zhou, Jianjun Zhang, Qingshan KongAbstract:A core-shell structured polysulfonamide@polyvinylidene fluoride-co-hexafluoropropene composite nonwoven separator was exploited for lithium ion battery via coaxial electrospinning technique for enhanced safety characteristic of battery. Polysulfonamide (PSA) and polyvinylidene fluoride-co-hexafluoropropene (PVDF-HFP) were used as the inner (core) and outer (shell) layer, respectively. Compared with the commercial polypropylene (PP) separator, the PSA@PVDF-HFP composite nonwoven separator manifested higher porosity, better electrolyte wettability and superior thermal stability. Moreover, it was demonstrated that the assembled cell with PSA@PVDF-HFP composite nonwoven separator displayed superior rate capability and better cycling capacity retention than those of PP separator. Notably, these attractive characteristics would endow PSA@PVDF-HFP composite nonwoven a promising separator for high power lithium ion battery. (C) 2013 The Electrochemical Society.
Elisabeth Rieger - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted desulfonylation of Polysulfonamides toward polypropylenimine
ACS Macro Letters, 2018Co-Authors: Elisabeth Rieger, Tassilo Gleede, Angelika Manhart, Markus Lamla, Friederik R. WurmAbstract:Linear polyethylenimine (L-PEI) has been the gold standard for gene delivery and is typically prepared by hydrolysis from poly(2-oxazoline)s. Recently, also the anionic polymerization of activated aziridines was reported as a potential pathway toward linear and well-defined polyamines. However, only sulfonamide-activated aziridines so far undergo the living anionic polymerization and their desulfonylation was only reported scarcely. This is mainly due to the relatively high stability of the sulfonamides and the drastic change in solubility during the desulfonylation. Herein, we investigated the desulfonylation of such poly(aziridine)s prepared from tosylated or mesylated propyleneimine to afford linear polypropylenimine (L-PPI) as an alternative to L-PEI. Different desulfonylation strategies for tosylated (Ts) and mesylated (Ms) PPI were studied. The reductive cleavage of the sulfonamide with sodium bis(2-methoxy ethoxy) aluminum hydride yielded 80% of deprotected amine groups. Quantitative conversion to ...
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Microwave-Assisted Desulfonylation of Polysulfonamides toward Polypropylenimine
2018Co-Authors: Elisabeth Rieger, Tassilo Gleede, Angelika Manhart, Markus Lamla, Friederik R. WurmAbstract:Linear polyethylenimine (L-PEI) has been the gold standard for gene delivery and is typically prepared by hydrolysis from poly(2-oxazoline)s. Recently, also the anionic polymerization of activated aziridines was reported as a potential pathway toward linear and well-defined polyamines. However, only sulfonamide-activated aziridines so far undergo the living anionic polymerization and their desulfonylation was only reported scarcely. This is mainly due to the relatively high stability of the sulfonamides and the drastic change in solubility during the desulfonylation. Herein, we investigated the desulfonylation of such poly(aziridine)s prepared from tosylated or mesylated propyleneimine to afford linear polypropylenimine (L-PPI) as an alternative to L-PEI. Different desulfonylation strategies for tosylated (Ts) and mesylated (Ms) PPI were studied. The reductive cleavage of the sulfonamide with sodium bis(2-methoxy ethoxy) aluminum hydride yielded 80% of deprotected amine groups. Quantitative conversion to L-PPI was obtained, when the tosylated PPI was hydrolyzed under acidic conditions with pTsOH under microwave (MW) irradiation. The same treatment removed 90% of the mesyl groups from the mesylated PPI analog. The MW-assisted acidic hydrolysis represents a fast, inexpensive and easy approach in comparison to other methods, where complex reaction conditions and tedious purifications are major drawbacks, however some chain scission may occur. The high purity of the obtained products, in combination with the versatility of the activated aziridine chemistry, demonstrate many advantages of our strategy, especially for future biomedical implementations
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4 styrenesulfonyl 2 methyl aziridine the first bivalent aziridine monomer for anionic and radical polymerization
Macromolecular Chemistry and Physics, 2018Co-Authors: Tassilo Gleede, Elisabeth Rieger, Tatjana Homannmuller, Frederik R WurmAbstract:4-Styrenesulfonyl-(2-methyl)aziridine (StMAz), the first orthogonal aziridine monomer, for both anionic ring-opening and radical polymerization is presented. Both polymerization pathways are accessible without using protective groups. Aza-anionic ring-opening polymerization (A-AROP) of StMAz and other methyl-aziridine derivatives provide multifunctional polyaziridines. Molecular weights between 3000 and 13 000 g mol−1 are obtained with low molecular weight dispersities (Ð = 1.1). The amount of vinyl groups in linear polyaziridines from A-AROP depends on the monomer/comonomer ratio. The vinyl groups of P(StMAz)- homo- or copolymers are entirely convertible by thiol-ene addition. This allows modification with multiple functional groups. Free radical polymerization of StMAz leads to polyalkylenes with aziridine side groups, which are known to be efficiently addressable via nucleophiles. Polysulfonamides still belong to a rather new class of polymers accessible by anionic polymerization. Enlarging the scope of postpolymerization modifications on polyaziridines/-sulfonamides is important for further macromolecular architectures. The aziridine and the vinyl group are combined to develop the first orthogonal monomer for aza-anionic polymerization and radical polymerization.
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the living anionic polymerization of activated aziridines a systematic study of reaction conditions and kinetics
Polymer Chemistry, 2017Co-Authors: Elisabeth Rieger, Tassilo Gleede, Angelika Manhart, Katja Weber, Manfred Wagner, Frederik R WurmAbstract:“A living race” – polymerization kinetics of anionic polymerizations depends strongly on the solvent polarity and reactivity of the growing chain end. Both the carb- and oxyanionic polymerization is under control at the university lab and on the industrial level, however, no information for the aza-anionic polymerization of aziridines has been reported systematically. This work studies the polymerization of two activated aziridines (2-methyl-N-mesylaziridine (MsMAz) and 2-methyl-N-tosylaziridine (TsMAz)) by real-time 1H NMR spectroscopy. This technique allows monitoring the consumption of the monomer precisely during the polymerization under different conditions (temperature, solvent, initiator and counter-ion variation). From the experimental data, propagation rate constants (kp) were calculated and analyzed. The polymerization of MsMAz was monitored at different temperatures (20, 50, and 100 °C). The increase of temperature increases the speed of polymerization, but keeps the living behavior. Furthermore, the influence of different solvents on the polymerization speed was examined, proving solvating solvents such as DMSO and DMF as the fastest solvents. Two different initiators, the potassium salts of N,N′-(1,4-phenylenebis(methylene))dimethanesulfonamide (BnBis(NHMs)), the first bifunctional initiator for the AROP of aziridines, and of N-benzyl-sulfonamide (BnNHMs) were compared. The variation of the counter ions Li+, Na+, K+, and Cs+ (generated from the respective bis(trimethylsilyl)amide salts) proved successful polymerization of both monomers with all counter ions. Slight variations have been detected in the order: Cs+ > Li+ > Na+ > K+, which is in strong contrast for the AROP of epoxides, shows a strong gegenion-dependent kinetic profile. This allows the use of commercially available initiators, such as BuLi for the synthesis of PAz. With these results in hand, the azaanionic polymerization can be used as a valuable tool in the family of anionic polymerization for the preparation of structurally diverse Polysulfonamides and polyamines under a broad variety of conditions, while maintaining the living behavior.
Zhihong Liu - One of the best experts on this subject based on the ideXlab platform.
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cellulose polysulfonamide composite membrane as a high performance lithium ion battery separator
ACS Sustainable Chemistry & Engineering, 2014Co-Authors: Qingshan Kong, Jianjun Zhang, Liping Yue, Zhihong Liu, X P Wang, Rongzhan Liu, Yulong Duan, Guanglei CuiAbstract:Battery separators have drawn considerable attention due to their vital roles for the safety and electrochemical performance of lithium-ion batteries. In this paper, the cellulose/polysulfonamide composite membrane was successfully fabricated from a mixture of microfibrillar cellulose and polysulfonamide via a facile papermaking process. And its potential application was explored as a high performance lithium-ion battery separator by characterizing their electrolyte wettability, heat tolerance, and electrochemical properties. Lithium cobalt oxide/graphite cells using the separator displayed better capacity retention ratios of 85% after 100 cycles and superior rate capability compared with those of a commercial polypropylene separator. Furthermore, the lithium iron phosphate/lithium half cell using cellulose/polysulfonamide separator exhibited stable charge–discharge capability even at 120 °C. It was demonstrated that the composite separator possessed an enhanced thermal dimensional stability. This researc...
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A Heat-Resistant Silica Nanoparticle Enhanced Polysulfonamide Nonwoven Separator for High-Performance Lithium Ion Battery
Journal of The Electrochemical Society, 2013Co-Authors: Jianjun Zhang, Xinhong Zhou, Qingshan Kong, Liping Yue, Zhihong Liu, Chuanjian Zhang, Shuping Pang, Xuejiang Wang, Jianhua Yao, Guanglei CuiAbstract:In this paper, a heat-resistant silica nanoparticle enhanced polysulfonamide nonwoven separator has been successfully explored by electrospinning method followed by a dip-coating process for high-performance lithium ion battery. In comparison to Celgard 2500 separator, silica nanoparticle enhanced polysulfonamide nonwoven separator possessed higher porosity, better electrolyte uptake, superior thermal resistance and higher ionic conductivity. The lithium cobalt oxide (LiCoO2)/graphite cell using silica nanoparticle enhanced polysulfonamide nonwoven separator displayed better rate capability and superior capacity retention than that of Celgard 2500 separator. Moreover, silica nanoparticle enhanced polysulfonamide nonwoven separator based lithium iron phosphate (LiFePO4)/lithium(Li) cell exhibited stable charge-discharge capability and satisfactory cycle performance even at a high temperature of 120 degrees C. These advanced characteristics would boost the application of silica nanoparticle enhanced polysulfonamide nonwoven separator for high-power lithium ion battery. (C) 2013 The Electrochemical Society. All rights reserved.