A battery drivable low-voltage transparent lightly antimony（Sb）-doped SnO2 nanowire electric-double-layer （EDL） field-effect transistor （FET） is fabricated on an ITO glass substrate at room temperature. An ultra...A battery drivable low-voltage transparent lightly antimony（Sb）-doped SnO2 nanowire electric-double-layer （EDL） field-effect transistor （FET） is fabricated on an ITO glass substrate at room temperature. An ultralow operation voltage of 1 V is obtained on account of an untralarge specific gate capacitance （- 2.14 μF/cm2） directly bound up with mobile ions-induced EDL （sandwiched between the top and bottom electrodes） effect. The transparent FET shows excellent electric characteristics with a field-effect mobility of 54.43 cm2/V. s, current on/off ration of 2 × 104, and subthreshold gate voltage swing （S = dVgs/d（logIds）） of 140 mV/decade. The threshold voltage Yth （0.1 V） is estimated which indicates that the SnO2 namowire transistor operates in an n-type enhanced mode. Such a low-voltage transparent nanowire transistor gated by a microporous SiO2-based solid electrolyte is very promising for battery-powered portable nanoscale sensors.展开更多
A solid state reaction method was used to prepare the perovskite-structured compounds BaZrl-xYxO3-a （x=0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3）. The X-ray diffraction （XRD） pattern indicated that the target perovsldte ...A solid state reaction method was used to prepare the perovskite-structured compounds BaZrl-xYxO3-a （x=0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3）. The X-ray diffraction （XRD） pattern indicated that the target perovsldte phases were obtained. With increasing Y con- centration the unit cell parameters of BaZrl-xYxO3-a samples were expanded, and Y doping became more difficult. However, high synthesis temperature is helpful to promote Y doping. The SEM results showed that the samples exhibited poor sinterability with in- creasing Y-doping content. Thermal gravimetric （TG） curves analysis showed the more mass decreasing of BaZrl-xYxO3-a （0≤x≤0.3） samples at high temperature with more Y doping and more proton introducing. The electrochemical impedance spectra （EIS） of specimens showed that conductivities of BaZrl_xYxO3（0≤x≤0.3） increased with increasing temperature from 300 to 900 ℃ in wet air. At 900 ℃, the conductivity of BaZrl-xYxO3-a （0≤x≤0.3） first increased with increasing doped amount of Y, and reached the high- est value of 1.07x 104 S/cm when x was 0.2, then decreased gradually with further increasing Y content. At 600 ℃, BaZr0.75Y0.2503-a displayed the highest conductivity, while the conductivity of BaZro.rYo.303-a was the highest at 300 ℃. The results indicated that there should be an optimum Y doping concentration yielding the highest conductivity at a constant temperature, and the optimum Y doping concentration should increase in the humidity atmosphere as the temperature decreases. So increasing the Y-doping concen- tration is helpful to improve the conductivities of BaZrl-xYxO3-a materials at low temperature.展开更多
The steel contains a small amount of hydrogen which will escape during the heat treatment.The hydrogen pressure in 16MnRE steel was investigated with a hydrogen sensor,which used SrCe0.95Yb0.05O3-α proton conductor a...The steel contains a small amount of hydrogen which will escape during the heat treatment.The hydrogen pressure in 16MnRE steel was investigated with a hydrogen sensor,which used SrCe0.95Yb0.05O3-α proton conductor as a solid electrolyte,YHx＋YH2z as a solid state reference electrode and Ni wire as electrode constructing a hydrogen concentration cell,shown as Ni｜YHx＋YH2z ｜SrCe0.95Yb0.05O3-α ｜[H] steel ｜Ni.The response time of sensor is less than 10s.The relational expression of hydrogen partial pressure with temperatures was determined using two shape proton conductors.The results showed the regularity in experimental temperature range,and the hydrogen partial pressure increased as its temperature was raised.展开更多
(NH4)3PW12O40 and(NH4)3PW12O40-H3PO4 composites have been synthesized by precipitation method.Their phase compositions,thermal stability and morphologies have been investigated.The synthesized composites maintain the ...(NH4)3PW12O40 and(NH4)3PW12O40-H3PO4 composites have been synthesized by precipitation method.Their phase compositions,thermal stability and morphologies have been investigated.The synthesized composites maintain the same structures as pure(NH4)3PW12O40 where phosphoric acid is preserved in residual space of the"spongy crystals"of(NH4)3PW12O40.FT-IR spectra confirm the strong interactions between phosphoric acid and Keggin ions.Pristine(NH4)3PW12O40 shows poor conductivity in air at high temperatures and strongly depends on water molecules for proton transport.The composites exhibit a much higher conductivity compared with pure(NH4)3PW12O40.The highest conductivity achieved is 0.14 S/cm at 170℃where continuous channels based on phosphoric acid for proton transportation are probably established.Such high conductivity of(NH4)3PW12O40-H3PO4 composites implies promising applications in fuel cells and other electrochemical devices.展开更多
BaZr1-xScxO3-0.5x (x=0.07,0.10,0.13,0.16) powders were prepared by solid-state reaction method,and ZnO was used as sintering aid.Samples with different amount of ZnO additive were sintered at 1450·C for 6 h in ai...BaZr1-xScxO3-0.5x (x=0.07,0.10,0.13,0.16) powders were prepared by solid-state reaction method,and ZnO was used as sintering aid.Samples with different amount of ZnO additive were sintered at 1450·C for 6 h in air.Single cubic perovskite phase proton conductors were obtained.Conductivity was measured by electrochemical workstation.It was shown that Sc doping could increase conductivity through enhancing the carrier concentration in the material,but excessive Sc content might decrease the carrier concentration because of its charge compensation.ZnO had an influence on carrier concentration and mobility and affected the electrical conductivity.2 mol% ZnO and 13 mol% ScO1.5 doped sample showed the highest DC conductivity of 3.6×10-3 S·cm-1 tested at 800·C in wet hydrogen atmosphere.展开更多
Two types of disposable EMF hydrogen sensors for measurements ofsolute contents of liquid metals in situ in metal-refining processesand their general principles are introduced. The way to design newelectrochemical sen...Two types of disposable EMF hydrogen sensors for measurements ofsolute contents of liquid metals in situ in metal-refining processesand their general principles are introduced. The way to design newelectrochemical sensors and the direction to develop new protonicconductors as new electrochemical sensors are discussed. Thefeasibility of protonic conductors worked as hydrogen pump innon-ferrous metal refining processes is discussed as well.展开更多
Hybrid proton conducting membranes of poly（vinyl alcohol） （PVA） and phosphomolybdic acid （PMA） were prepared by solution casting method. The effect of PMA doping and PVA crosslinking density on the membrane prop...Hybrid proton conducting membranes of poly（vinyl alcohol） （PVA） and phosphomolybdic acid （PMA） were prepared by solution casting method. The effect of PMA doping and PVA crosslinking density on the membrane properties and proton conductivity were investigated. The crosslinking reaction between the hydroxyl group of PVA and the aldehyde group of glutaraldehyde （GA） was characterized by IR spectroscopy. Proton conductivity of the membranes increases with an increase in concentration of the doped PMA and also with an increase in crosslinking density of the membranes. Proton conductivity results indicate that a significant amount of PMA was maintained in the membranes even after several hours of immersion in water. A maximum conductivity of 0.0101 S cm^-1 was obtained for the membrane with 33.3 wt% PMA and crosslinking density of 5.825 mol%. X-ray diffraction studies were carried out to investigate the influence of PMA doping and crosslinking density on the nature of the membranes. These properties make them very good candidates for polymer electrolyte membranes for direct methanol fuel cell application.展开更多
Heterogeneous composite BaZr0.9Y0.1O2.95/Na2SO4 was designed and fabricated with Y-doped BaZrO3 as matrix and Na2SO4 as dispersant by conventional powder processing to improve the total conductivity of barium zirconat...Heterogeneous composite BaZr0.9Y0.1O2.95/Na2SO4 was designed and fabricated with Y-doped BaZrO3 as matrix and Na2SO4 as dispersant by conventional powder processing to improve the total conductivity of barium zirconate. The electrical conduction of the composite was studied by electrical and electrochemical methods. Microstructure of the heterogeneous composite was examined by SEM. The experimewtal results show that the protonic conductivity of Y-doped BaZrO3 is greatly improved upon incorporating Na2SO4 in the material. Microstructure observation indicates that a multiphase structure with Na2SO4 disperses at the grain boundaries of BaZr0.1Y0.9O2.95. Electromotive force （EMF） measurements under fuel cell conditions reveal that the total ionic transport number of the composite is more than 0.9 at 750 ℃.展开更多
We have fabricated the fuel cell based on the tissue derived biomaterial “collagen” and investigated its proton transfer. It was found that “collagen” becomes the electrolyte of fuel cell in the humidified conditi...We have fabricated the fuel cell based on the tissue derived biomaterial “collagen” and investigated its proton transfer. It was found that “collagen” becomes the electrolyte of fuel cell in the humidified condition. The power density of the fuel cell becomes typically 8.6 W/m2 in the 80% humidity. Further, these results indicate that collagen exhibits proton conductivity in the humidified condition. Both of proton conductivity and dielectric constant increase by the increase of humidity. From the analyses of the frequency dependence of AC conductivity, it was found that proton conductivity and the dielectric dispersion observed in the humidified condition are caused by the formation of the water bridge, which is bonded with the collagen peptide chain. Considering that hydration induces the formation of the water bridge and that increases proton conductivity and dielectric constant, it is deduced that proton transfer in the fuel cell based on collagen is caused by the breaking and rearrangement of hydrogen bond in the water bridge.展开更多
In order to investigate a key factor for the appearance of proton conductivity in chitin-chitosan mixed compounds, the chitin-chitosan mixed compounds (chitin)x(chitosan)1-x were prepared and these proton conductiviti...In order to investigate a key factor for the appearance of proton conductivity in chitin-chitosan mixed compounds, the chitin-chitosan mixed compounds (chitin)x(chitosan)1-x were prepared and these proton conductivities have been investigated. DC proton conductivity σ is obtained from Nyquist plot of impedance measurement data, and the relationship between σ and mixing ratio x has been made clear. It was found that the x dependence of σ is non-monotonous. That is, σ shows the anomalous behavior, and has peaks around x = 0.4 and 0.75. This result indicates that there exist optimal conditions for the realization of high-proton conductivity in the chitin-chitosan mixed compound in which the number of acetyl groups is different. From the FT-IR measurement, we have found that the behavior of proton conductivity in (chitin)x(chitosan)1-x is determined by the amount of water content changed by x. Using these results, proton conductivity, which is important for the application of conducting polymers in chitin-chitosan mixed compounds, will be able to be easily controlled by adjusting the mixing ratio x.展开更多
We have fabricated a fuel cell based on the tissue-derived biomaterial “chitin”, and investigated its proton conductivity. It was found that chitin becomes the electrolyte of the fuel cell in the humidified conditio...We have fabricated a fuel cell based on the tissue-derived biomaterial “chitin”, and investigated its proton conductivity. It was found that chitin becomes the electrolyte of the fuel cell in the humidified condition, and power density of the fuel cell using chitin electrolyte becomes typically 1.35 mW/cm2 at the 100% relative humidity. This result is the first result showing that the polysaccharide obtained from nature becomes the fuel cell electrolyte. Moreover, this result indicates that chitin is proton conductor in the humidified condition. In the chitin sheet plane, proton conductivity in chitin is observed approximately 0.1 S/m. Further, it was also found that chitin has the anisotropic proton conductivity. The proton conductivity along the chitin fiber direction is higher than that perpendicular to the chitin fiber direction. From these results, it is deduced that the formation of water bridges accompanied by hydration plays an important role in the appearance of proton conductivity in chitin.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 10874042)
文摘A battery drivable low-voltage transparent lightly antimony（Sb）-doped SnO2 nanowire electric-double-layer （EDL） field-effect transistor （FET） is fabricated on an ITO glass substrate at room temperature. An ultralow operation voltage of 1 V is obtained on account of an untralarge specific gate capacitance （- 2.14 μF/cm2） directly bound up with mobile ions-induced EDL （sandwiched between the top and bottom electrodes） effect. The transparent FET shows excellent electric characteristics with a field-effect mobility of 54.43 cm2/V. s, current on/off ration of 2 × 104, and subthreshold gate voltage swing （S = dVgs/d（logIds）） of 140 mV/decade. The threshold voltage Yth （0.1 V） is estimated which indicates that the SnO2 namowire transistor operates in an n-type enhanced mode. Such a low-voltage transparent nanowire transistor gated by a microporous SiO2-based solid electrolyte is very promising for battery-powered portable nanoscale sensors.
基金Project supported by National Natural Science Foundation of China （51074038, 51274057） and National High Technology Research and Development Program of China （2013AA030902）
文摘A solid state reaction method was used to prepare the perovskite-structured compounds BaZrl-xYxO3-a （x=0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3）. The X-ray diffraction （XRD） pattern indicated that the target perovsldte phases were obtained. With increasing Y con- centration the unit cell parameters of BaZrl-xYxO3-a samples were expanded, and Y doping became more difficult. However, high synthesis temperature is helpful to promote Y doping. The SEM results showed that the samples exhibited poor sinterability with in- creasing Y-doping content. Thermal gravimetric （TG） curves analysis showed the more mass decreasing of BaZrl-xYxO3-a （0≤x≤0.3） samples at high temperature with more Y doping and more proton introducing. The electrochemical impedance spectra （EIS） of specimens showed that conductivities of BaZrl_xYxO3（0≤x≤0.3） increased with increasing temperature from 300 to 900 ℃ in wet air. At 900 ℃, the conductivity of BaZrl-xYxO3-a （0≤x≤0.3） first increased with increasing doped amount of Y, and reached the high- est value of 1.07x 104 S/cm when x was 0.2, then decreased gradually with further increasing Y content. At 600 ℃, BaZr0.75Y0.2503-a displayed the highest conductivity, while the conductivity of BaZro.rYo.303-a was the highest at 300 ℃. The results indicated that there should be an optimum Y doping concentration yielding the highest conductivity at a constant temperature, and the optimum Y doping concentration should increase in the humidity atmosphere as the temperature decreases. So increasing the Y-doping concen- tration is helpful to improve the conductivities of BaZrl-xYxO3-a materials at low temperature.
基金supported by the National Natural Science Foundation of China under Grant No.50774018
文摘The steel contains a small amount of hydrogen which will escape during the heat treatment.The hydrogen pressure in 16MnRE steel was investigated with a hydrogen sensor,which used SrCe0.95Yb0.05O3-α proton conductor as a solid electrolyte,YHx＋YH2z as a solid state reference electrode and Ni wire as electrode constructing a hydrogen concentration cell,shown as Ni｜YHx＋YH2z ｜SrCe0.95Yb0.05O3-α ｜[H] steel ｜Ni.The response time of sensor is less than 10s.The relational expression of hydrogen partial pressure with temperatures was determined using two shape proton conductors.The results showed the regularity in experimental temperature range,and the hydrogen partial pressure increased as its temperature was raised.
基金supported financially by the National Natural Science Foundation of China(No.21401142,51972233)the Natural Science Foundation of Shanghai(No.19ZR1459200)+3 种基金the National 1000-Plan Programthe Shanghai Science and Technology Commission(No.14DZ2261100)the South Taihu Elite Projectthe Fundamental Research Funds for the Central Universities.
文摘(NH4)3PW12O40 and(NH4)3PW12O40-H3PO4 composites have been synthesized by precipitation method.Their phase compositions,thermal stability and morphologies have been investigated.The synthesized composites maintain the same structures as pure(NH4)3PW12O40 where phosphoric acid is preserved in residual space of the"spongy crystals"of(NH4)3PW12O40.FT-IR spectra confirm the strong interactions between phosphoric acid and Keggin ions.Pristine(NH4)3PW12O40 shows poor conductivity in air at high temperatures and strongly depends on water molecules for proton transport.The composites exhibit a much higher conductivity compared with pure(NH4)3PW12O40.The highest conductivity achieved is 0.14 S/cm at 170℃where continuous channels based on phosphoric acid for proton transportation are probably established.Such high conductivity of(NH4)3PW12O40-H3PO4 composites implies promising applications in fuel cells and other electrochemical devices.
基金financially supported by the National Natural Science Foundation of China (No.50872090)Guizhou Province-University Scientific and Technological Cooperation Program (No.[2011]7002)
文摘BaZr1-xScxO3-0.5x (x=0.07,0.10,0.13,0.16) powders were prepared by solid-state reaction method,and ZnO was used as sintering aid.Samples with different amount of ZnO additive were sintered at 1450·C for 6 h in air.Single cubic perovskite phase proton conductors were obtained.Conductivity was measured by electrochemical workstation.It was shown that Sc doping could increase conductivity through enhancing the carrier concentration in the material,but excessive Sc content might decrease the carrier concentration because of its charge compensation.ZnO had an influence on carrier concentration and mobility and affected the electrical conductivity.2 mol% ZnO and 13 mol% ScO1.5 doped sample showed the highest DC conductivity of 3.6×10-3 S·cm-1 tested at 800·C in wet hydrogen atmosphere.
基金This project is financially Supported by the National Natural Science Foundation of China (No. 20101006)Postdoctoral Foundation of China, and Shanghai Postdoctoral Foundation
文摘Two types of disposable EMF hydrogen sensors for measurements ofsolute contents of liquid metals in situ in metal-refining processesand their general principles are introduced. The way to design newelectrochemical sensors and the direction to develop new protonicconductors as new electrochemical sensors are discussed. Thefeasibility of protonic conductors worked as hydrogen pump innon-ferrous metal refining processes is discussed as well.
文摘Hybrid proton conducting membranes of poly（vinyl alcohol） （PVA） and phosphomolybdic acid （PMA） were prepared by solution casting method. The effect of PMA doping and PVA crosslinking density on the membrane properties and proton conductivity were investigated. The crosslinking reaction between the hydroxyl group of PVA and the aldehyde group of glutaraldehyde （GA） was characterized by IR spectroscopy. Proton conductivity of the membranes increases with an increase in concentration of the doped PMA and also with an increase in crosslinking density of the membranes. Proton conductivity results indicate that a significant amount of PMA was maintained in the membranes even after several hours of immersion in water. A maximum conductivity of 0.0101 S cm^-1 was obtained for the membrane with 33.3 wt% PMA and crosslinking density of 5.825 mol%. X-ray diffraction studies were carried out to investigate the influence of PMA doping and crosslinking density on the nature of the membranes. These properties make them very good candidates for polymer electrolyte membranes for direct methanol fuel cell application.
基金Funded by the National Natural Science Foundation of China(No. 50872090)
文摘Heterogeneous composite BaZr0.9Y0.1O2.95/Na2SO4 was designed and fabricated with Y-doped BaZrO3 as matrix and Na2SO4 as dispersant by conventional powder processing to improve the total conductivity of barium zirconate. The electrical conduction of the composite was studied by electrical and electrochemical methods. Microstructure of the heterogeneous composite was examined by SEM. The experimewtal results show that the protonic conductivity of Y-doped BaZrO3 is greatly improved upon incorporating Na2SO4 in the material. Microstructure observation indicates that a multiphase structure with Na2SO4 disperses at the grain boundaries of BaZr0.1Y0.9O2.95. Electromotive force （EMF） measurements under fuel cell conditions reveal that the total ionic transport number of the composite is more than 0.9 at 750 ℃.
文摘We have fabricated the fuel cell based on the tissue derived biomaterial “collagen” and investigated its proton transfer. It was found that “collagen” becomes the electrolyte of fuel cell in the humidified condition. The power density of the fuel cell becomes typically 8.6 W/m2 in the 80% humidity. Further, these results indicate that collagen exhibits proton conductivity in the humidified condition. Both of proton conductivity and dielectric constant increase by the increase of humidity. From the analyses of the frequency dependence of AC conductivity, it was found that proton conductivity and the dielectric dispersion observed in the humidified condition are caused by the formation of the water bridge, which is bonded with the collagen peptide chain. Considering that hydration induces the formation of the water bridge and that increases proton conductivity and dielectric constant, it is deduced that proton transfer in the fuel cell based on collagen is caused by the breaking and rearrangement of hydrogen bond in the water bridge.
文摘In order to investigate a key factor for the appearance of proton conductivity in chitin-chitosan mixed compounds, the chitin-chitosan mixed compounds (chitin)x(chitosan)1-x were prepared and these proton conductivities have been investigated. DC proton conductivity σ is obtained from Nyquist plot of impedance measurement data, and the relationship between σ and mixing ratio x has been made clear. It was found that the x dependence of σ is non-monotonous. That is, σ shows the anomalous behavior, and has peaks around x = 0.4 and 0.75. This result indicates that there exist optimal conditions for the realization of high-proton conductivity in the chitin-chitosan mixed compound in which the number of acetyl groups is different. From the FT-IR measurement, we have found that the behavior of proton conductivity in (chitin)x(chitosan)1-x is determined by the amount of water content changed by x. Using these results, proton conductivity, which is important for the application of conducting polymers in chitin-chitosan mixed compounds, will be able to be easily controlled by adjusting the mixing ratio x.
文摘We have fabricated a fuel cell based on the tissue-derived biomaterial “chitin”, and investigated its proton conductivity. It was found that chitin becomes the electrolyte of the fuel cell in the humidified condition, and power density of the fuel cell using chitin electrolyte becomes typically 1.35 mW/cm2 at the 100% relative humidity. This result is the first result showing that the polysaccharide obtained from nature becomes the fuel cell electrolyte. Moreover, this result indicates that chitin is proton conductor in the humidified condition. In the chitin sheet plane, proton conductivity in chitin is observed approximately 0.1 S/m. Further, it was also found that chitin has the anisotropic proton conductivity. The proton conductivity along the chitin fiber direction is higher than that perpendicular to the chitin fiber direction. From these results, it is deduced that the formation of water bridges accompanied by hydration plays an important role in the appearance of proton conductivity in chitin.
