JAEA
  • help
  • PC | SP
  • JP | EN
          
Refine your search：     
Report No.
 - 
Clear All
Search Results: Records 1-20 displayed on this page of 21

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Imidazolium-based anion exchange membranes for alkaline anion fuel cells; Elucidation of the morphology and the interplay between the morphology and properties

Zhao, Y.; Yoshimura, Kimio; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Koizumi, Satoshi*; Szekely, N.*; Radulescu, A.*; Richter, D.*; Maekawa, Yasunari

Soft Matter, 12(5), p.1567 - 1578, 2016/02

https://doi.org/10.1039/C5SM02724A
 Times Cited Count：27 Percentile：79.79(Chemistry, Physical)

Journal Articles

Imidazolium cation based anion-conducting electrolyte membranes prepared by radiation induced grafting for direct hydrazine hydrate fuel cells

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Yamamoto, Kazuya*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

Journal of the Electrochemical Society, 161(9), p.F889 - F893, 2014/06

https://doi.org/10.1149/2.0511409jes
 Times Cited Count：21 Percentile：59.69(Electrochemistry)

Graft-type anion-conducting electrolyte membranes (AEMs) with imidazolium cations on graft polymers were synthesized through radiation-induced graft polymerization of ${it N}$-vinylimidazole (NVIm) on poly(ethylene-co-tetrafluoroethylene) (ETFE) films, followed by ${it N}$-propylation and ion-exchange reactions. The ${it N}$-propylation proceeded quantitatively, whereas the ion-exchange reactions in 1 M KOH at 60$$^{circ}$$C were accompanied by partial $$beta$$-elimination of the imidazolium cations(AEM2), which exhibited an ion-exchange capacity (IEC) of 0.85 mmol g$$^{-1}$$ and ionic conductivity of 10 mS cm$$^{-1}$$. AEM2 showed alkaline stability at 60$$^{circ}$$C but it gradually degraded at 80$$^{circ}$$C for ca. 150 h. The copolymer-type AEM (AEM3) with an IEC of 1.20 mmol g$$^{-1}$$ was prepared through the copolymerization of NVIm with styrene on ETFE films, followed by the same ${it N}$-propylation and ion-exchange reactions. AEM3 was shown higher alkaline durability in 1 M KOH at 80$$^{circ}$$C. As a result, it exhibited higher conductivity ($$>$$10 mS cm$$^{-1}$$) for 250 h. Therefore, alkylimidazolium cations in copolymer grafts are a promising anion conducting group for alkaline-durable AEMs. A maximum power density of 75 mW cm$$^{-2}$$ is obtained for AEM3 in a direct hydrazine hydrate fuel cell.

Journal Articles

Alkaline durable anion exchange membranes based on graft-type fluoropolymer films for hydrazine hydrate fuel cell

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Maekawa, Yasunari; Yamamoto, Kazuya*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*

ECS Transactions, 50(2), p.2075 - 2081, 2012/10

https://doi.org/10.1149/05002.2075ecs

no abstracts in English

Oral presentation

Preparation of anion-exchange membranes for fuel cell applications by $$gamma$$-ray pre-irradiation grafting; Effect of the structure of quaternary ammonium ions

Koshikawa, Hiroshi; Yamaki, Tetsuya; Asano, Masaharu; Yoshimura, Kimio; Maekawa, Yasunari; Yamamoto, Kazuya*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*

no journal, , 

We investigated the effect of the length of the linear chain on the structure of quaternary ammonium ions on the membrane properties such as durability of ion conductivity. Graft polymerization was performed by immersing the pre-irradiated ETFE film in the CMS solution. The ETFE-g-CMS film was then quaternized in four different tertiary amines, that is, trimethylamine (n = 1), dimethylethylamine (n = 2), n-butyldimethylamine (n = 4) and n-hexyldimethylamine (n = 6) solutions. The n dependence of the OH$$^{-}$$ conductivity and chemical durability, which was represented by a residual percentage of the conductivity after treatment with a Fenton solution. When n increased from 1 to 6, the OH$$^{-}$$ conductivity decreased slightly, but it still stayed 20 mS/cm for n = 6. The chemical durability seemed to increase eight-fold at the same time. The chemical attack by hydroxyl radicals on the quaternary ammonium ions would be controlled by hydrophobicity and steric hindrance of the alkyl group.

Oral presentation

Synthesis of novel anion conductive membranes by radiation-induced grafting; Basicity effect

Yoshimura, Kimio; Sinnananchi, W.; Koshikawa, Hiroshi; Yamaki, Tetsuya; Maekawa, Yasunari; Yamamoto, Kazuya*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*

no journal, , 

no abstracts in English

Oral presentation

Development of anion-exchange membranes by radiation grafting; Effect of crosslinker for swelling

Asano, Masaharu; Koshikawa, Hiroshi; Yamaki, Tetsuya; Maekawa, Yasunari; Yamamoto, Kazuya*; Sampei, Fumihiro*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*

no journal, , 

no abstracts in English

Oral presentation

Development of anion-exchange membranes by radiation grafting technique

Asano, Masaharu; Koshikawa, Hiroshi; Yamaki, Tetsuya; Yoshimura, Kimio; Maekawa, Yasunari; Yamamoto, Kazuya*; Sampei, Fumihiro*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; et al.

no journal, , 

no abstracts in English

Oral presentation

Alkaline durable anion exchange membranes synthesized by radiation-induced grafting

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Sampei, Fumihiro*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

no journal, , 

no abstracts in English

Oral presentation

Synthesis of alkaline durable anion exchange membranes by radiation-induced grafting for hydrazine hydrate fuel cell

Yoshimura, Kimio; Sinananwanich, W.*; Koshikawa, Hiroshi; Asano, Masaharu; Yamaki, Tetsuya; Maekawa, Yasunari; Yamamoto, Kazuya*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; et al.

no journal, , 

no abstracts in English

Oral presentation

Graft-type anion conducting membranes consisting of iminium cation for alkaline durable fuel cells

Maekawa, Yasunari; Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Yamamoto, Kazuya*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*

no journal, , 

Anion-exchange membranes (AEM) for hydrazine fuel cells, in which non precious metals are used as an electrode catalyst, have been developing by radiation techniques. AEMs having polyvinylimidazolium grafts were synthesized by radiation-induced graft polymerization of N-vinylimidazole or the copolymerizaiton with styrene onto ETFE film, followed by N-alkylation and ion exchange reactions. The alkaline durability of the membranes was evaluated in 1M KOH at 80 $$^{circ}$$C. The AEM consisting of the homopolymer grafts showed alkaline stability at 80 $$^{circ}$$C for ca. 150 hours. In contrast, the copolymer (1:1 molar ratio) grafts type AEM kept its ion conductivity above 10 mS/cm in 1M KOH at 80 $$^{circ}$$C for 250 h. The alkylimidazolium group in the copolymer grafts is a promising anion exchange group in AEMs for highly alkaline durable fuel cells.

Oral presentation

Preparation of anion-exchange membranes using ionizing radiation and their cell testing

Koshikawa, Hiroshi; Yamaki, Tetsuya; Asano, Masaharu; Yoshimura, Kimio; Maekawa, Yasunari; Yamamoto, Kazuya*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*

no journal, , 

We prepared anion-exchange membranes based on an ethylene-tetrafluoroethylene copolymer by $$gamma$$-ray-induced graft polymerization of chloromethylstyrene (CMS) and the subsequent quaternization reaction. The crosslinker effect was investigated in terms of membrane preparation and performance of a hydrazine fuel cell. The quaternization ratio appeared to decrease as the concentration of divinylbenzene (DVB) in the CMS grafting solution increased. Importantly, the crosslinker lowered the water uptake of the resulting membranes in the Cl$$^{-}$$ and OH$$^{-}$$ forms, possibly thereby restricting excessive swelling during the fuel-cell operation.

Oral presentation

Preparation of anion-exchange membranes for fuel cell applications by $$gamma$$-ray pre-irradiation grafting; Effect of the structure of quaternary ammonium ions

Koshikawa, Hiroshi; Asano, Masaharu; Yamaki, Tetsuya; Yoshimura, Kimio; Maekawa, Yasunari; Yamamoto, Kazuya*; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*

no journal, , 

We investigated the effect of a linear carbon chain length (n) in quaternary ammonium ions, on the durability of ion conductivity of anion exchange membrane. The poly(ethylene-co-tetrafluoroethylene) grafted chloromethylstyrene film was quaternized in four different tertiary amines, that is, trimethylamine (n=1), dimethylethylamine (n=2), n-butyldimethylamine (n=4) and n-hexyldimethylamine (n=6) solutions. The n dependence of ion conductivity and chemical durability, which was represented by a residual percentage of the conductivity after treatment with a Fenton solution (3% hydrogen peroxide+ 4 ppm iron sulfate) at 80 $$^{circ}$$C for 2 h. When n increased from 1 to 6, the ion conductivity decreased slightly, but it still stayed 20 mS/cm for n = 6. Interestingly, the chemical durability seemed to increase eight-fold at the same time. The chemical attack by hydroxyl radicals on the quaternary ammonium ions would be controlled by hydrophobicity and steric hindrance of the alkyl group.

Oral presentation

Synthesis of alkaline durable anion exchange membranes by radiation-induced grafting for hydrazine hydrate fuel cell

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

no journal, , 

no abstracts in English

Oral presentation

4(5)-vinylimidazolium based anion exchange membranes prepared by radiation-induced grafting for hydrazine hydrate fuel cell

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

no journal, , 

no abstracts in English

Oral presentation

Development of alkaline durable anion exchange membranes prepared by radiation-induced grafting for Pt-free hydrazine hydrate fuel cell

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

no journal, , 

no abstracts in English

Oral presentation

4(5)-vinylimidazolium based anion-conducting electrolyte membrane prepared by radiation-induced grafting for hydrazine hydrate fuel cell

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

no journal, , 

Anion-conducting electrolyte membrane fuel cells (AEMFCs) especially in direct hydrazine fuel cells have recently received considerable attention. Due to high temperature and highly basic operating condition, it is required to develop alkaline durable AEMs. In this work, we synthesized the AEM based on a 4(5)-vinylimidazole (4VIm) monomer by radiation-induced grafting and subsequent ${it N}$-alkylation and ion exchange reactions (${bf AEM2}$) because 4VIm does not possess $$beta$$-protons, leading to a Hoffman elimination reaction, which is the main degradation route in 1-vinylimidazolium-grafted AEM (${bf AEM1}$). The alkaline stability of AEMs was estimated by monitoring the change in conductivity of AEMs in 1 M KOH at 60$$^{circ}$$C. As a result, the conductivity of ${bf AEM1}$ suddenly decreased within few hours, while the initial decrement of conductivity of ${bf AEM2}$ was clearly suppressed. It clearly showed that the prevention of a Hoffman elimination reaction enhanced the alkaline durability of the imidazolium-type AEM.

Oral presentation

Hierarchical structures and fuel cell properties of imidazolium-containing anion conducting polymer electrolyte membranes prepared by radiation-induced grafting

Yoshimura, Kimio; Zhao, Y.; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Koizumi, Satoshi*; Maekawa, Yasunari

no journal, , 

Anion conducting polymer electrolyte membranes (AEMs) having poly 2-methyl-1-vinylimidazolium grafts were synthesized by radiation-induced graft coplymerizaiton of 2-methyl-1-vinylimidazole with styrene onto an ETFE film, followed by N-alkylation and ion exchange reactions. The excellent long-term stability of the prepared AEMs was confirmed in 1M KOH at 80$$^{circ}$$C. The graft-type AEM with an ion exchange capacity of 1.80 mmol/g showed a maximum power density of 210 mW cm$$^{-2}$$ in a direct hydrazine hydrate fuel cell test. The contrast variation experiment in small-angle neutron scattering measurement displayed the advantageous three-phase structures, consisting of crystalline, amorphous hydrophobic, and amorphous hydrophilic domains.

Oral presentation

Alkaline durable 2-methyl-1-vinylimidazolium-based anion exchange membranes prepared by radiation-induced grafting for hydrazine hydrate fuel cells

Yoshimura, Kimio; Koshikawa, Hiroshi; Yamaki, Tetsuya; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

no journal, , 

Since anion-conducting electrolyte membrane fuel cells (AEMFCs) such as direct hydrazine fuel cells operated under high temperature and highly basic condition, it is required to develop alkaline durable AEMs. In this work, we synthesized AEM with poly 2-methyl-1-vinylimidazolium grafts by radiation-induced graft coplymerizaiton to protect 2-position of imidazolium ring from alkaline hydroxide ion attack. The AEM with an ion-exchange capacity (IEC) of 1.80 mmol g$$^{-1}$$ exhibited ionic conductivity of 123 mS cm$$^{-1}$$ at 60$$^{circ}$$C. The durability of the membrane was evaluated. The excellent long-term alkaline stability of the prepared AEM was confirmed in 1M KOH at 80$$^{circ}$$C. Therefore, the protection of 2-position by methyl group suppresses ring opening degradation reactions, resulting in the improvement of the alkaline durability of imidazolium-type AEMs.

Oral presentation

Structure-property relationships in graft-type polymer electrolyte membranes studied by complemental small angle neutron/X-ray scattering analyses

Maekawa, Yasunari; Zhao, Y.; Yoshimura, Kimio; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Koizumi, Satoshi*

no journal, , 

no abstracts in English

Oral presentation

Development of radiation grafted anion-conducting electrolyte membranes and application to hydrazine hydrate fuel cells

Yoshimura, Kimio; Shishitani, Hideyuki*; Yamaguchi, Susumu*; Tanaka, Hirohisa*; Maekawa, Yasunari

no journal, , 

no abstracts in English

21 (Records 1-20 displayed on this page)