The Experts below are selected from a list of 1221 Experts worldwide ranked by ideXlab platform
Jingtao Wang - One of the best experts on this subject based on the ideXlab platform.
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polyelectrolyte microcapsules as ionic liquid reservoirs within ionomer membrane to confer high anhydrous proton conductivity
Journal of Power Sources, 2015Co-Authors: Haoqin Zhang, Jingtao Wang, Wenjia Wu, Yifan Li, Bing ZhangAbstract:Abstract Herein, novel composite membranes are prepared by embedding methacrylic acid polyelectrolyte microcapsules (PMCs) into sulfonated poly(ether ether ketone) (SPEEK) matrix, followed by impregnating imidazole-type ionic liquids (ILs). Within the composite membrane, the lumens of PMCs act as IL reservoirs, which provide large space for IL storage and thus significantly elevate the IL uptake. The IL leaching measurement suggests that the cross-linked shells of PMCs manipulate the IL release, endowing the composite membrane with high IL retention. Moreover, the high IL retention renders the composite membrane more anhydrous hopping sites (e.g., the imidazole groups on IL and the acid-base pairs between imidazole and sulfonic acid groups), imparting a facilitated proton conduction via Grotthuss Mechanism. In particular, the composite membrane containing 12% PMCs achieves a high anhydrous proton conductivity of 33.7 mS cm −1 at 150 ° C. The same membrane also exhibits a surprising steady-state IL retention of 36.9% after leaching in liquid water.
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anhydrous proton exchange membrane of sulfonated poly ether ether ketone enabled by polydopamine modified silica nanoparticles
Electrochimica Acta, 2015Co-Authors: Jingtao Wang, Haoqin Zhang, Liping Zhao, Huiling Chen, Yifan LiAbstract:Abstract Novel anhydrous proton exchange membrane is (PEM) facilely prepared by embedding dopamine-modified silica nanoparticles (DSiOis 2 ) into sulfonated poly (ether ether ketone) (SPEEK) polymer matrix. DSiO 2 bearing NH 2 / NH groups are synthesized inspired by the bioadhesion principle, which are uniformly dispersed within SPEEK membrane due to the good interfacial compatibility. The interfacial electrostatic attractions render unique rearrangement of the nanophase-separated structure and the chain packing of the resultant hybrid membranes. As a result, the thermal and mechanical stabilities as well as structural stability of the hybrid membranes are enhanced when compared to SPEEK control membrane. On the other hand, induced by the attractions, acid–base pairs are formed at the SPEEK/DSiOarewere 2 interface, where fast proton transfer via Grotthuss Mechanism is expected. These features confer much higher proton conductivities on the DSiO 2 -filled membranes under both hydrated and anhydrous conditions, compared to those of the SPEEK control membrane and SiO 2 -filled membranes. Particularly, the hybrid membrane with 15 wt% DSiO 2 achieve the highest conductivities of 4.52achieveachieved × 10 −3 S cm −1 at 120 °C under anhydrous condition, which is much higher than the SPEEK control membrane and the commercial Nafion membrane (0.1iswas × 10 −3 S cm −1 ). The membrane with 9 wt% DSiO 2 show an open cell potential of 0.98showshowed V and an optimum power density of 111.7 mW cm −2 , indicative of its potential application in fuel cell under anhydrous condition.
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polydopamine modified graphene oxide nanocomposite membrane for proton exchange membrane fuel cell under anhydrous conditions
Journal of Materials Chemistry, 2014Co-Authors: Jingtao Wang, Haoqin Zhang, Tao Zhang, Bing Zhang, Shaokui Cao, Jindun LiuAbstract:A new approach to the facile preparation of anhydrous proton exchange membrane (PEM) enabled by artificial acid–base pairs is presented herein. Inspired by the bioadhesion of mussel, polydopamine-modified graphene oxide (DGO) sheets bearing –NH2 and –NH– groups are fabricated and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare the nanocomposite membrane. The DGO sheets are interconnected and homogeneously dispersed in SPEEK matrix, which provides unique rearrangement of the nanophase-separated structure and chain packing of nanocomposite membrane through interfacial electrostatic attractions. These attractions meanwhile induce the generation of acid–base pairs along the SPEEK–DGO interface, which then serve as long-range and low-energy-barrier pathways for proton hopping, imparting an enhanced proton transfer via the Grotthuss Mechanism. In particular, under both hydrated and anhydrous conditions, the nanocomposite membrane exhibits much higher proton conductivity than the polymer control membrane. The enhanced proton conductivity results in the nanocomposite membrane having elevated cell performances under 120 °C and hydrous conditions, yielding a 47% increase in maximum current density and a 38% increase in maximum power density. Together with the stable conduction property, these results guarantee the nanocomposite membrane's promising prospects in high-performance fuel cell under anhydrous and elevated temperature conditions.
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polydopamine modified graphene oxide nanocomposite membrane for proton exchange membrane fuel cell under anhydrous conditions
Journal of Materials Chemistry, 2014Co-Authors: Yakun He, Jingtao Wang, Haoqin Zhang, Tao Zhang, Bing ZhangAbstract:A new approach to the facile preparation of anhydrous proton exchange membrane (PEM) enabled by artificial acid–base pairs is presented herein. Inspired by the bioadhesion of mussel, polydopamine-modified graphene oxide (DGO) sheets bearing –NH2 and –NH– groups are fabricated and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare the nanocomposite membrane. The DGO sheets are interconnected and homogeneously dispersed in SPEEK matrix, which provides unique rearrangement of the nanophase-separated structure and chain packing of nanocomposite membrane through interfacial electrostatic attractions. These attractions meanwhile induce the generation of acid–base pairs along the SPEEK–DGO interface, which then serve as long-range and low-energy-barrier pathways for proton hopping, imparting an enhanced proton transfer via the Grotthuss Mechanism. In particular, under both hydrated and anhydrous conditions, the nanocomposite membrane exhibits much higher proton conductivity than the polymer control membrane. The enhanced proton conductivity results in the nanocomposite membrane having elevated cell performances under 120 °C and hydrous conditions, yielding a 47% increase in maximum current density and a 38% increase in maximum power density. Together with the stable conduction property, these results guarantee the nanocomposite membrane's promising prospects in high-performance fuel cell under anhydrous and elevated temperature conditions.
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enhanced proton conduction of chitosan membrane enabled by halloysite nanotubes bearing sulfonate polyelectrolyte brushes
Journal of Membrane Science, 2014Co-Authors: Haoqin Zhang, Bing Zhang, Yakun He, Jingtao WangAbstract:Abstract Currently, enhancing the proton conductivity is one challenge for chitosan (CS, an industrial waste around the world) membrane to work as proton exchange membrane for direct methanol fuel cell. In this study, halloysite nanotubes bearing sulfonate polyelectrolyte brushes (SHNTs) are synthesized via distillation–precipitation polymerization and then incorporated into CS matrix to fabricate nanohybrid membranes. The membranes are characterized using field emission scanning electron microscope, fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, and mechanical tester. It is found that SHNTs generate strong electrostatic attractions to CS chains, which inhibit the chain mobility and thus enhance the thermal and mechanical stabilities of nanohybrid membranes. The results of water uptake, area swelling, proton conductivity, and activation energy reveal that the high aspect nanotube and long polyelectrolyte brush allow SHNTs to construct continuous and wide pathways, along which sulfonic acid–amide acid–base pairs are formed and work as low-barrier proton-hoping sites, imparting an enhanced proton transfer via Grotthuss Mechanism. In such a way, the proton conductivity of CS membrane is obviously enhanced, and 15% SHNTs can afford a 60% enhancement in conductivity to the nanohybrid membrane, particularly. Moreover, the methanol permeability and selectivity of the as-prepared membranes are investigated in detail.
Haoqin Zhang - One of the best experts on this subject based on the ideXlab platform.
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polyelectrolyte microcapsules as ionic liquid reservoirs within ionomer membrane to confer high anhydrous proton conductivity
Journal of Power Sources, 2015Co-Authors: Haoqin Zhang, Jingtao Wang, Wenjia Wu, Yifan Li, Bing ZhangAbstract:Abstract Herein, novel composite membranes are prepared by embedding methacrylic acid polyelectrolyte microcapsules (PMCs) into sulfonated poly(ether ether ketone) (SPEEK) matrix, followed by impregnating imidazole-type ionic liquids (ILs). Within the composite membrane, the lumens of PMCs act as IL reservoirs, which provide large space for IL storage and thus significantly elevate the IL uptake. The IL leaching measurement suggests that the cross-linked shells of PMCs manipulate the IL release, endowing the composite membrane with high IL retention. Moreover, the high IL retention renders the composite membrane more anhydrous hopping sites (e.g., the imidazole groups on IL and the acid-base pairs between imidazole and sulfonic acid groups), imparting a facilitated proton conduction via Grotthuss Mechanism. In particular, the composite membrane containing 12% PMCs achieves a high anhydrous proton conductivity of 33.7 mS cm −1 at 150 ° C. The same membrane also exhibits a surprising steady-state IL retention of 36.9% after leaching in liquid water.
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anhydrous proton exchange membrane of sulfonated poly ether ether ketone enabled by polydopamine modified silica nanoparticles
Electrochimica Acta, 2015Co-Authors: Jingtao Wang, Haoqin Zhang, Liping Zhao, Huiling Chen, Yifan LiAbstract:Abstract Novel anhydrous proton exchange membrane is (PEM) facilely prepared by embedding dopamine-modified silica nanoparticles (DSiOis 2 ) into sulfonated poly (ether ether ketone) (SPEEK) polymer matrix. DSiO 2 bearing NH 2 / NH groups are synthesized inspired by the bioadhesion principle, which are uniformly dispersed within SPEEK membrane due to the good interfacial compatibility. The interfacial electrostatic attractions render unique rearrangement of the nanophase-separated structure and the chain packing of the resultant hybrid membranes. As a result, the thermal and mechanical stabilities as well as structural stability of the hybrid membranes are enhanced when compared to SPEEK control membrane. On the other hand, induced by the attractions, acid–base pairs are formed at the SPEEK/DSiOarewere 2 interface, where fast proton transfer via Grotthuss Mechanism is expected. These features confer much higher proton conductivities on the DSiO 2 -filled membranes under both hydrated and anhydrous conditions, compared to those of the SPEEK control membrane and SiO 2 -filled membranes. Particularly, the hybrid membrane with 15 wt% DSiO 2 achieve the highest conductivities of 4.52achieveachieved × 10 −3 S cm −1 at 120 °C under anhydrous condition, which is much higher than the SPEEK control membrane and the commercial Nafion membrane (0.1iswas × 10 −3 S cm −1 ). The membrane with 9 wt% DSiO 2 show an open cell potential of 0.98showshowed V and an optimum power density of 111.7 mW cm −2 , indicative of its potential application in fuel cell under anhydrous condition.
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polydopamine modified graphene oxide nanocomposite membrane for proton exchange membrane fuel cell under anhydrous conditions
Journal of Materials Chemistry, 2014Co-Authors: Jingtao Wang, Haoqin Zhang, Tao Zhang, Bing Zhang, Shaokui Cao, Jindun LiuAbstract:A new approach to the facile preparation of anhydrous proton exchange membrane (PEM) enabled by artificial acid–base pairs is presented herein. Inspired by the bioadhesion of mussel, polydopamine-modified graphene oxide (DGO) sheets bearing –NH2 and –NH– groups are fabricated and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare the nanocomposite membrane. The DGO sheets are interconnected and homogeneously dispersed in SPEEK matrix, which provides unique rearrangement of the nanophase-separated structure and chain packing of nanocomposite membrane through interfacial electrostatic attractions. These attractions meanwhile induce the generation of acid–base pairs along the SPEEK–DGO interface, which then serve as long-range and low-energy-barrier pathways for proton hopping, imparting an enhanced proton transfer via the Grotthuss Mechanism. In particular, under both hydrated and anhydrous conditions, the nanocomposite membrane exhibits much higher proton conductivity than the polymer control membrane. The enhanced proton conductivity results in the nanocomposite membrane having elevated cell performances under 120 °C and hydrous conditions, yielding a 47% increase in maximum current density and a 38% increase in maximum power density. Together with the stable conduction property, these results guarantee the nanocomposite membrane's promising prospects in high-performance fuel cell under anhydrous and elevated temperature conditions.
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polydopamine modified graphene oxide nanocomposite membrane for proton exchange membrane fuel cell under anhydrous conditions
Journal of Materials Chemistry, 2014Co-Authors: Yakun He, Jingtao Wang, Haoqin Zhang, Tao Zhang, Bing ZhangAbstract:A new approach to the facile preparation of anhydrous proton exchange membrane (PEM) enabled by artificial acid–base pairs is presented herein. Inspired by the bioadhesion of mussel, polydopamine-modified graphene oxide (DGO) sheets bearing –NH2 and –NH– groups are fabricated and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare the nanocomposite membrane. The DGO sheets are interconnected and homogeneously dispersed in SPEEK matrix, which provides unique rearrangement of the nanophase-separated structure and chain packing of nanocomposite membrane through interfacial electrostatic attractions. These attractions meanwhile induce the generation of acid–base pairs along the SPEEK–DGO interface, which then serve as long-range and low-energy-barrier pathways for proton hopping, imparting an enhanced proton transfer via the Grotthuss Mechanism. In particular, under both hydrated and anhydrous conditions, the nanocomposite membrane exhibits much higher proton conductivity than the polymer control membrane. The enhanced proton conductivity results in the nanocomposite membrane having elevated cell performances under 120 °C and hydrous conditions, yielding a 47% increase in maximum current density and a 38% increase in maximum power density. Together with the stable conduction property, these results guarantee the nanocomposite membrane's promising prospects in high-performance fuel cell under anhydrous and elevated temperature conditions.
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enhanced proton conduction of chitosan membrane enabled by halloysite nanotubes bearing sulfonate polyelectrolyte brushes
Journal of Membrane Science, 2014Co-Authors: Haoqin Zhang, Bing Zhang, Yakun He, Jingtao WangAbstract:Abstract Currently, enhancing the proton conductivity is one challenge for chitosan (CS, an industrial waste around the world) membrane to work as proton exchange membrane for direct methanol fuel cell. In this study, halloysite nanotubes bearing sulfonate polyelectrolyte brushes (SHNTs) are synthesized via distillation–precipitation polymerization and then incorporated into CS matrix to fabricate nanohybrid membranes. The membranes are characterized using field emission scanning electron microscope, fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, and mechanical tester. It is found that SHNTs generate strong electrostatic attractions to CS chains, which inhibit the chain mobility and thus enhance the thermal and mechanical stabilities of nanohybrid membranes. The results of water uptake, area swelling, proton conductivity, and activation energy reveal that the high aspect nanotube and long polyelectrolyte brush allow SHNTs to construct continuous and wide pathways, along which sulfonic acid–amide acid–base pairs are formed and work as low-barrier proton-hoping sites, imparting an enhanced proton transfer via Grotthuss Mechanism. In such a way, the proton conductivity of CS membrane is obviously enhanced, and 15% SHNTs can afford a 60% enhancement in conductivity to the nanohybrid membrane, particularly. Moreover, the methanol permeability and selectivity of the as-prepared membranes are investigated in detail.
Bing Zhang - One of the best experts on this subject based on the ideXlab platform.
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polyelectrolyte microcapsules as ionic liquid reservoirs within ionomer membrane to confer high anhydrous proton conductivity
Journal of Power Sources, 2015Co-Authors: Haoqin Zhang, Jingtao Wang, Wenjia Wu, Yifan Li, Bing ZhangAbstract:Abstract Herein, novel composite membranes are prepared by embedding methacrylic acid polyelectrolyte microcapsules (PMCs) into sulfonated poly(ether ether ketone) (SPEEK) matrix, followed by impregnating imidazole-type ionic liquids (ILs). Within the composite membrane, the lumens of PMCs act as IL reservoirs, which provide large space for IL storage and thus significantly elevate the IL uptake. The IL leaching measurement suggests that the cross-linked shells of PMCs manipulate the IL release, endowing the composite membrane with high IL retention. Moreover, the high IL retention renders the composite membrane more anhydrous hopping sites (e.g., the imidazole groups on IL and the acid-base pairs between imidazole and sulfonic acid groups), imparting a facilitated proton conduction via Grotthuss Mechanism. In particular, the composite membrane containing 12% PMCs achieves a high anhydrous proton conductivity of 33.7 mS cm −1 at 150 ° C. The same membrane also exhibits a surprising steady-state IL retention of 36.9% after leaching in liquid water.
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polydopamine modified graphene oxide nanocomposite membrane for proton exchange membrane fuel cell under anhydrous conditions
Journal of Materials Chemistry, 2014Co-Authors: Jingtao Wang, Haoqin Zhang, Tao Zhang, Bing Zhang, Shaokui Cao, Jindun LiuAbstract:A new approach to the facile preparation of anhydrous proton exchange membrane (PEM) enabled by artificial acid–base pairs is presented herein. Inspired by the bioadhesion of mussel, polydopamine-modified graphene oxide (DGO) sheets bearing –NH2 and –NH– groups are fabricated and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare the nanocomposite membrane. The DGO sheets are interconnected and homogeneously dispersed in SPEEK matrix, which provides unique rearrangement of the nanophase-separated structure and chain packing of nanocomposite membrane through interfacial electrostatic attractions. These attractions meanwhile induce the generation of acid–base pairs along the SPEEK–DGO interface, which then serve as long-range and low-energy-barrier pathways for proton hopping, imparting an enhanced proton transfer via the Grotthuss Mechanism. In particular, under both hydrated and anhydrous conditions, the nanocomposite membrane exhibits much higher proton conductivity than the polymer control membrane. The enhanced proton conductivity results in the nanocomposite membrane having elevated cell performances under 120 °C and hydrous conditions, yielding a 47% increase in maximum current density and a 38% increase in maximum power density. Together with the stable conduction property, these results guarantee the nanocomposite membrane's promising prospects in high-performance fuel cell under anhydrous and elevated temperature conditions.
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polydopamine modified graphene oxide nanocomposite membrane for proton exchange membrane fuel cell under anhydrous conditions
Journal of Materials Chemistry, 2014Co-Authors: Yakun He, Jingtao Wang, Haoqin Zhang, Tao Zhang, Bing ZhangAbstract:A new approach to the facile preparation of anhydrous proton exchange membrane (PEM) enabled by artificial acid–base pairs is presented herein. Inspired by the bioadhesion of mussel, polydopamine-modified graphene oxide (DGO) sheets bearing –NH2 and –NH– groups are fabricated and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare the nanocomposite membrane. The DGO sheets are interconnected and homogeneously dispersed in SPEEK matrix, which provides unique rearrangement of the nanophase-separated structure and chain packing of nanocomposite membrane through interfacial electrostatic attractions. These attractions meanwhile induce the generation of acid–base pairs along the SPEEK–DGO interface, which then serve as long-range and low-energy-barrier pathways for proton hopping, imparting an enhanced proton transfer via the Grotthuss Mechanism. In particular, under both hydrated and anhydrous conditions, the nanocomposite membrane exhibits much higher proton conductivity than the polymer control membrane. The enhanced proton conductivity results in the nanocomposite membrane having elevated cell performances under 120 °C and hydrous conditions, yielding a 47% increase in maximum current density and a 38% increase in maximum power density. Together with the stable conduction property, these results guarantee the nanocomposite membrane's promising prospects in high-performance fuel cell under anhydrous and elevated temperature conditions.
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enhanced proton conduction of chitosan membrane enabled by halloysite nanotubes bearing sulfonate polyelectrolyte brushes
Journal of Membrane Science, 2014Co-Authors: Haoqin Zhang, Bing Zhang, Yakun He, Jingtao WangAbstract:Abstract Currently, enhancing the proton conductivity is one challenge for chitosan (CS, an industrial waste around the world) membrane to work as proton exchange membrane for direct methanol fuel cell. In this study, halloysite nanotubes bearing sulfonate polyelectrolyte brushes (SHNTs) are synthesized via distillation–precipitation polymerization and then incorporated into CS matrix to fabricate nanohybrid membranes. The membranes are characterized using field emission scanning electron microscope, fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, and mechanical tester. It is found that SHNTs generate strong electrostatic attractions to CS chains, which inhibit the chain mobility and thus enhance the thermal and mechanical stabilities of nanohybrid membranes. The results of water uptake, area swelling, proton conductivity, and activation energy reveal that the high aspect nanotube and long polyelectrolyte brush allow SHNTs to construct continuous and wide pathways, along which sulfonic acid–amide acid–base pairs are formed and work as low-barrier proton-hoping sites, imparting an enhanced proton transfer via Grotthuss Mechanism. In such a way, the proton conductivity of CS membrane is obviously enhanced, and 15% SHNTs can afford a 60% enhancement in conductivity to the nanohybrid membrane, particularly. Moreover, the methanol permeability and selectivity of the as-prepared membranes are investigated in detail.
Jindun Liu - One of the best experts on this subject based on the ideXlab platform.
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polydopamine modified graphene oxide nanocomposite membrane for proton exchange membrane fuel cell under anhydrous conditions
Journal of Materials Chemistry, 2014Co-Authors: Jingtao Wang, Haoqin Zhang, Tao Zhang, Bing Zhang, Shaokui Cao, Jindun LiuAbstract:A new approach to the facile preparation of anhydrous proton exchange membrane (PEM) enabled by artificial acid–base pairs is presented herein. Inspired by the bioadhesion of mussel, polydopamine-modified graphene oxide (DGO) sheets bearing –NH2 and –NH– groups are fabricated and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare the nanocomposite membrane. The DGO sheets are interconnected and homogeneously dispersed in SPEEK matrix, which provides unique rearrangement of the nanophase-separated structure and chain packing of nanocomposite membrane through interfacial electrostatic attractions. These attractions meanwhile induce the generation of acid–base pairs along the SPEEK–DGO interface, which then serve as long-range and low-energy-barrier pathways for proton hopping, imparting an enhanced proton transfer via the Grotthuss Mechanism. In particular, under both hydrated and anhydrous conditions, the nanocomposite membrane exhibits much higher proton conductivity than the polymer control membrane. The enhanced proton conductivity results in the nanocomposite membrane having elevated cell performances under 120 °C and hydrous conditions, yielding a 47% increase in maximum current density and a 38% increase in maximum power density. Together with the stable conduction property, these results guarantee the nanocomposite membrane's promising prospects in high-performance fuel cell under anhydrous and elevated temperature conditions.
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enhanced proton conductivity of sulfonated poly ether ether ketone membrane embedded by dopamine modified nanotubes for proton exchange membrane fuel cell
Fuel Cells, 2013Co-Authors: Haoqin Zhang, Jingtao Wang, Tao Zhang, F Pei, Jindun LiuAbstract:Design and fabrication of alternative proton exchange membrane (PEM) with high proton conductivity is crucial to the commercial application of PEM fuel cell. Inspired by the bioadhesion principle, dopamine-modified halloysite nanotubes (DHNTs) bearing –NH2 and –NH– groups are facilely synthesized by directly immersing natural halloysite nanotubes (HNTs) into dopamine aqueous solution under mild conditions. DHNTs are then embedded into sulfonated poly(ether ether ketone) (SPEEK) matrix to prepare hybrid membranes. HNTs-filled hybrid membranes are prepared for comparison. The microstructure and physicochemical properties of the membranes are extensively investigated. Fourier transform infrared analysis implies that ordered acid–base pairs (e.g., –S–O–…+H–HN–, –S–O–…+H–N–) are formed at SPEEK–DHNT interface through strong electrostatic interaction. In such a way, continuous surface-induced ion-channels emerge along DHNTs. Although the incorporation of DHNTs reduces the channel size, water uptake, and area swelling of the hybrid membranes, which in turn would reduce the vehicle-type proton transfer, the acid–base pairs create continuous pathways for fast proton transfer with low energy barrier via Grotthuss Mechanism. Consequently, DHNT-filled hybrid membrane with 15% DHNTs achieves a 30% increase in proton conductivity and a 52% increase in peak power density of single cell when compared with SPEEK control membrane, particularly.
Barbara Sieklucka - One of the best experts on this subject based on the ideXlab platform.
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dehydration triggered charge transfer and high proton conductivity in h3o niiii cyclam mii cn 6 m ru os cyanide bridged chains
Inorganic Chemistry, 2018Co-Authors: Mateusz Reczynski, Shin-ichi Ohkoshi, Beata Nowicka, Christian Nather, Marcin Koziel, Koji Nakabayashi, Barbara SiekluckaAbstract:The coexistence of dehydration-driven charge transfer, magnetic interactions, and high proton conductivity was found in two bimetallic alternating CN-bridged chains {(H3O)[NiIII(cyclam)][MII(CN)6]·5H2O} n (M = Ru (1), Os (2); cyclam = 1,4,8,11-tetraazacyclotetradecane). Dehydration of these materials causes structural transformation and triggers charge transfer between the metal centers: NiIII-NC-MII → NiII-NC-MIII. The CT process, whose extent is tuned by the change of the anionic building block, causes significant increase of magnetic moment, appearance of antiferromagnetic interactions, and noticeable changes in color. The high conductivity values of σ = 1.09 × 10-3 (1) and 1.12 × 10-3 S cm-1 (2) at 295 K and 100% relative humidity allow the classification of the materials as superionic conductors. The proton conduction occurs according to the Grotthuss Mechanism as a hopping of protons between H-bonded water molecules due to the presence of the H3O+ ions, which compensate negative charge of the coordination chains.
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Dehydration-Triggered Charge Transfer and High Proton Conductivity in (H3O)[NiIII(cyclam)][MII(CN)6] (M = Ru, Os) Cyanide-Bridged Chains
2018Co-Authors: Mateusz Reczyński, Shin-ichi Ohkoshi, Beata Nowicka, Koji Nakabayashi, Christian Näther, Marcin Kozieł, Barbara SiekluckaAbstract:The coexistence of dehydration-driven charge transfer, magnetic interactions, and high proton conductivity was found in two bimetallic alternating CN-bridged chains {(H3O)[NiIII(cyclam)][MII(CN)6]·5H2O}n (M = Ru (1), Os (2); cyclam = 1,4,8,11-tetraazacyclotetradecane). Dehydration of these materials causes structural transformation and triggers charge transfer between the metal centers: NiIII–NC–MII → NiII–NC–MIII. The CT process, whose extent is tuned by the change of the anionic building block, causes significant increase of magnetic moment, appearance of antiferromagnetic interactions, and noticeable changes in color. The high conductivity values of σ = 1.09 × 10–3 (1) and 1.12 × 10–3 S cm–1 (2) at 295 K and 100% relative humidity allow the classification of the materials as superionic conductors. The proton conduction occurs according to the Grotthuss Mechanism as a hopping of protons between H-bonded water molecules due to the presence of the H3O+ ions, which compensate negative charge of the coordination chains
