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121.
Hybrid supercapacitor based on polyaniline doped with lithium salt and activated carbon electrodes 总被引:1,自引:1,他引:0
Polyaniline(PANI) nanofiber was synthesized by interfacial polymerization utilizing the interface between HCl and CCl4. The hybrid type supercapacitors (PLi/C) based on Li-doping polyaniline and activated carbon electrode were fabricated and
compared with the redox type capacitors (PLi/PLi) based on two uniformly Li-doping polyaniline electrodes. The electrochemical
performances of the two types of supercapacitors were characterized in non-aqueous electrolyte. PLi/C supercapacitors have
a wider effective energy storage potential range and a higher upper potential. At the same time, the PLi/C supercapacitor
exhibits a specific capacity of 120.93 F/g at initial discharge and retains 80% after 500 cycles. The ohmic internal resistance
(R
ES) of PLi/C supercapacitor is 5.0 Ω, which is smaller than that of PLi/PLi capacitor (5.5 Ω). Moreover, it can be seen that
Et4NBF4 organic solution is more suitable for using as organic electrolyte of PLi/C capacitor compared with organic solution containing
LiPF6.
Foundation item: Project(2008AA03Z207) supported by the National High-Tech Research and Development Program of China 相似文献
122.
A new anodic material of ternary Pb-0.8%Ag-(0–5.0%)Bi alloy for zinc electrowinning was obtained by doping Bi. The anodic
oxygen evolution potential, corrosion rate, surface products after polarization, and microstructures before and after polarization
were studied and compared with those of Pb-0.8%Ag anode used in industry. The results show the anodic overpotential decreases
with the increase of Bi content in the alloys. When the content of Bi is 1.0% (mass fraction), the anodic overpotential is
40–50 mV lower than that of Pb-0.8%Ag anode. While the corrosion rate decreases and then increases with the increase of Bi
content. The Pb-0.8%Ag-0.1%Bi anode has the lowest corrosion rate (0.090 6 mg/(h·cm2). Doping Bi influences the structure of the anodic layer, but does not change the phase. The Pb-0.8%Ag-1.0%Bi anode layer
is of a more fine-grained structure compared with Pb-0.8%Ag anode.
Foundation item: Project(2007SK2009) supported by the Science and Technology Research Project of Hunan Province, China 相似文献
123.
A room temperature physical model was used to study the bubble behavior and gas induced bath circulation in a drained aluminum reduction cell. By passing compressed argon through the penetrated Plexiglas box bottom plate immersed in water, gas evolution at the anode bottom surface was simulated. Bubble behavior and liquid flow field were studied and analysis was presented. Bath secondary recirculation was observed in the interpolar gap not the net rising flow as expected. Liquid driven by the bubbles forms small vortices along the interpolar gap with small mean and turbulent velocities and accordingly poor mass transfer. Secondary recirculation also exists between the slot and interpolar gap, part of the flow in the interpolar gap go to the slot with the bubbles and fluid at the bottom of the slot enters the interpolar gap directly without going to the center channel. The existence of the fluid secondary recirculation is very unfavorable to the alumina dissolution and dispersion. Increasing the anode tilt or gas flow rate, or decreasing the anode-cathode distance can make the secondary recirculation in the interpolar gap weak, however, will intensify the secondary recirculation between the slot and interpolar gap. 相似文献
124.
Preliminary testing of NiFe_2O_4-NiO as ceramic matrix of cermet inert anode in aluminum electrolysis 总被引:4,自引:0,他引:4
1 INTRODUCTIONTheideaofusinginertanodes(alsocallednon consumableoroxygen evolvinganodes)inaluminumproductionisasoldastheHall H啨roultprocess ,dat ingbacktothediscoveryofoneoftheinventors ,Hall[1] .Inertanodesareintendedtoreplacethecon sumablecarbonanodethatiscurrentlyused .Withacarbonanode ,thecellreactionisAl2 O3+ 3/ 2C =2Al+ 3/ 2CO2 (1)where acryolite basedmelt(Na3AlF6 AlF3 CaF2 )atnear 96 0℃servesassolventforthealumina .Withaninertanode ,thecellreactionwillbeAl2 … 相似文献
125.
(85Cu-15Ni)/(10NiO-NiFe2O4) cermets were prepared with Cu-Ni mixed powders as toughening metallic phase and 10NiO-NiFe2O4 as ceramic matrix. The phase composition, microstructure of composite and the effect of metallic phase content on bending strength, hardness, fracture toughness and thermal shock resistance were studied. X-ray diffraction analysis indicates the coexistence of (Cu-Ni), NiO and NiFe2O4 phases in the cermets. Within the content range of metallic phase from 0% to 20% (mass fraction), the maximal bending strength (176.4 MPa) and the minimal porosity (3.9%) of composite appear at the metallic phase content of 5%. The fracture toughness increases and Vickers' hardness decreases with increasing metal content. When the thermal shock temperature difference (At) is below 200 ℃, the loss rate of residual strength for 10NiO-NiFe2O4 ceramic is only 8%, but about 40% for (85Cu-15Ni)/(10NiO-NiFe2O4)cermets. As At is above 200 ℃, the residual strength sharply decreases for sample CN0 and falls slowly for samples CN5-CN20. 相似文献
126.
Densification of Ni-NiFe_2O_4 cermets for aluminum electrolysis 总被引:2,自引:1,他引:2
1INTRODUCTION Aluminumelectrolysisconsumesenormous energyandresources,andtheconsumptionwillbeconsiderablydecreasedbyintroductionofinert anodeandwettablecathode.However,underthe toughworkingconditionofaluminumelectrolysis,i.e.highlycorrosiveNa3AlF6Al2O3moltensalts athightemperature(940960℃),theinert anodesnecessaryforthesuccessfulproductionofaluminummighthavethefollowingproperties:be insolubleinafluoridemelt,beresistanttowards anodeoxygen,havegoodelectricalconductivity,possessadequatestr… 相似文献
127.
铝电解用NiFe2O4-Cu金属陶瓷惰性阳极的制备 总被引:16,自引:2,他引:16
以高温固相合成法合成的NiFe2O4陶瓷粉体和金属Cu粉为原料, 采用冷压-烧结法制备了Cu含量在5%~20%之间的NiFe2O4-Cu金属陶瓷惰性阳极, 研究了烧结气氛和烧结温度对其物相组成、微观形貌和基本物理性能的影响. 结果表明 通过控制烧结气氛中氧分压在NiO和Cu2O的离解反应平衡氧分压之间, 可以制备出具有目标物相组成的NiFe2O4-Cu金属陶瓷; 烧结温度和保温时间对所得NiFe2O4-Cu金属陶瓷的相对密度有较大影响; NiFe2O4和Cu之间的不润湿性限制了NiFe2O4-Cu金属陶瓷烧结温度的提高和保温时间的延长, 在保证金属相分布均匀且不溢出的前提下, 所制备的NiFe2O4-Cu金属陶瓷的相对密度较小; 金属相Cu含量越高, NiFe2O4-Cu金属陶瓷最高烧结温度越低、最长保温时间越短, 从而相对密度越低、孔隙率越高; 除了尽量降低金属相含量外, 还可向NiFe2O4-Cu金属陶瓷中添加其他金属如Ni和Co等, 以改善陶瓷相与金属相之间的润湿性, 以提高烧结温度, 进而提高其相对密度和耐腐蚀性能. 相似文献
128.
129.
以线性羧酸酯EA、EP和EB分别替代工业用1.0 mol/L LiPF6 EC/EMC/DMC(1:1:1,质量比)电解液中的DMC,配制了1.0 mol/L LiPF6 EC/EMC/EA(1:1:2,质量比)、1.0 mol/L LiPF6 EC/EMC/EP(1:1:2,质量比)和1.0mol/L Li PF6 EC/EMC/EB(1:1:2,质量比)3种包含线性羧酸酯的电解液,采用18650全电池研究线性羧酸酯作为电解液溶剂组元对锰酸锂-石墨电池低温性能的影响。结果表明,采用3种包含线性羧酸酯的电解液,电池在-20°C、5C倍率下放电容量保持率均大于93%,而采用工业用电解液时,电池无法在-20°C、5C倍率下放电。电化学阻抗谱分析表明,在低温下电池放电容量和放电能量衰减的主要原因是电荷转移阻抗随温度的降低而增大。在3种含线性羧酸酯的电解液中,使用1.0 mol/L LiPF6 EC/EMC/EA(1:1:2,质量比)电解液的电池因具有最低的电荷转移阻抗,表现出最好的电化学性能,在-40°C下放电容量保持率大于90%,在-60°C下放电容量保持率大于44.41%。 相似文献
130.
Two finite element(FE) models were built up for analysis of stress field in the lining of aluminum electrolysis cells. Distribution of sodium concentration in cathode carbon blocks was calculated by one FE model of a cathode block. Thermal stress field was calculated by the other slice model of the cell at the end of the heating-up. Then stresses coupling thermal and sodium expansion were considered after 30 d start-up. The results indicate that sodium penetrates to the bottom of the cathode block after 30 d start-up. The semi-graphitic carbon block has the largest stress at the thermal stage. After 30 d start-up the anthracitic carbon has the greatest sodium expansion stress and the graphitized carbon has the lowest sodium expansion stress. Sodium penetration can cause larger deformation and stress in the cathode carbon block than thermal expansion. 相似文献