电极间距对单室微生物燃料电池处理老龄垃圾渗滤液性能的影响

以体积分数为60%的老龄垃圾渗滤液为单室无膜空气阴极微生物燃料电池底物,考察电极间距分别为1、2、3、4、5 cm时电池产电性能及底物中物污染物的去除效果。结果表明,间距为2 cm时输出电压和最大功率密度最大,间距为4 cm时输出电压和最大功率密度最小;电极间距为1～3 cm时电池内阻随电极间距的增大而增大,而电极间距大于3 cm时电池内阻随电极间距的增大而减小。电极间距为2 cm时,微生物燃料电池(MFC)对老龄垃圾渗滤液中化学需氧量(COD)和氨氮去除率最高;5个电池的库伦效率分别为35.6%、27.6%、35.4%、14.9%和14.9%,单室无膜空气阴极MFC可在一定程度上提高老龄垃圾渗滤液的可生化性。     

生物阴极微生物燃料电池餐饮废水处理与发电性能研究

对比研究生物阴极微生物燃料电池与一般微生物燃料电池的废水处理与同步发电能力。以学校食堂餐饮废水为微生物燃料电池的底物,首先通过实验为微生物燃料电池选择合适的电子受体;其次,在采用较适宜电子受体的同等条件下,对生物阴极微生物燃料电池与一般微生物燃料电池处理餐饮废水的COD去除率及产电电流密度进行对比。实验结果表明,生物阴极微生物燃料电池处理餐饮废水的废水处理效果和发电能力均优于一般微生物燃料电池。     

活性炭与TiO_2混合催化镍基体生物阴极微生物燃料电池性能研究

以发泡镍为基体,柱状活性炭颗粒和Ti O2粉末均匀混合后作为催化剂涂覆在电极表面。将此复合电极作为双室生物阴极型MFC的电极,研究MFC的产电性能。结果表明:在运行周期内,系统最大输出电压可达到698.1 m V,稳定在500 m V以上的高电压输出时间为18 d;单位质子膜面积上可获得最大功率密度为183.33W/m4,质子膜的使用量明显减少,从而大大降低了MFC的产电成本。同时,阳极室对原生活污水COD去除率可达到74%,而库伦效率也可达到68.9%。试验结果表明,活性炭和Ti O2混合涂覆镍基体电极对双室生物阴极型MFC产电的催化效果良好。     

自主研发电化学治疗同轴电极与传统针式电极电解效应的对比研究

【摘要】 目的 用自主研发同轴电极和直针式电极电解含百里香酚蓝琼脂 ＮａＣｌ胶体系统模拟组织毁损，观察两者的电解效应，探讨自主研发同轴电极的应用价值。方法 采用百里香酚蓝琼脂 ＮａＣｌ胶体系统模拟组织。在实验中保持同轴电极和针式电极的接触面积、间距一致。随着阴极周围ＯＨ－的聚集，ｐＨ升高，阴极周围胶体会变为鲜艳的蓝色。将电流分为１．６、５．０、１０．０和２０ ｍＡ ４组进行实验，当电量累积到１、２、４、６、８库仑时测量阴极变色范围。结果 在恒定直流电作用下，各电流组同轴电极和针式电极的阴极周围的蓝色量均随电量增加而增加，各组内同轴电极和针式电极间的作用差异无统计学意义（Ｐ ＞０．０５）。在给予相同电量时，对各电流组阴极周围的变色体积进行组间比较，差异有统计学意义（Ｐ ＜ ０．０５），即电流越小作用时间越长，变色范围越大。结论 自制同轴电极与直针式电极具有相近的电解效果，可以替代直针式电极在电化学治疗中的应用。
     

乳制品废水作为微生物燃料电池底物的研究

用乳制品废水作为阳极室底物构建双室MFC反应器,厌氧池污泥混合菌作为生物催化剂,阴极室分别使用不同浓度的KMnO4溶液和溶解氧DO作为电子受体,调节MFC影响因子与该厌氧池对应,计算试验数据并与厌氧池废水处理效果进行比较,同时观察MFC的产电性能。结果表明:双室MFC的产电效率和稳定性随着阴极室KMnO4浓度的升高而提高;当溶解氧DO作为电子受体时,MFC产电性能较低,具有成本低、无污染的优点;经不同组MFC分别处理乳制品废水后,COD去除率均优于普通厌氧池的处理效果。     

泡沫镍空气阴极微生物燃料电池的产电特性

研究了泡沫镍阴极的制备和对单室微生物燃料电池产电性能的影响。研究发现,当阴极PTFE扩散层超过4+1层时,MFC的功率密度随扩散层数增加而逐渐下降;当阴极扩散层为五层(4+1层)时,微生物燃料电池最大功率密度最大,达到31.3 W/m3,电池的库仑效率为25%;当使用7+1层PTFE扩散层时,电池功率下降到25.6 W/m3;泡沫镍阴极厚度对阴极性能影响不大;研究发现,滚压后再涂一层扩散层能够抑制泡沫镍阴极的长期运行的析盐。     

碳电极浆料作为阴极材料的快速充放电铝离子电池北大核心CSCD

[EMIM]Cl基铝离子电池是一种具有前景的储能器件。由于其能量密度高、价格低廉、安全性高等特点有望成为下一代储能体系。本工作介绍了一种原本用于钙钛矿太阳能电池丝网印刷技术的可高倍率充放电的低温导电碳电极浆料,可在1000 mA/g的电流密度下,实现快速充放电,比容量保持在75 mAh/g左右,其充电倍率可达12 C。通过光学显微镜、扫描电子显微镜(SEM)、X射线衍射(XRD)以及比表面积分析等表征手段,对低温导电碳电极浆料、天然石墨片以及石墨烯作为阴极材料所组装的铝离子电池的性能进行了比较和分析,发现快速充放电主要是由于其特殊的表面形貌以及较大的比表面积所导致的。通过X射线衍射等测试也可证明低温导电碳电极浆料作为阴极材料的比容量高于其他阴极材料。实现了高充放电电流密度的铝离子电池。     

锌掺杂碳纳米管电极在微生物燃料电池中的应用

以锌掺杂碳纳米管电极为阳极,柔性石墨为阴极,葡萄糖为阳极室供给基质,构建双室微生物燃料电池(MFC),考察锌掺杂量、葡萄糖浓度、温度等因素对MFC产电性能及有机物降解率影响。结果表明,锌掺杂改性的碳纳米管,能加速阳极产电微生物膜形成,提高微生物膜产电能力。在外电阻2300Ω,葡萄糖浓度1257mg/L,Zn S掺杂量0.5 g,温度40℃时,MFC性能最佳,其最大输出电压为1030 m V,最大输出功率31.2 m W/m2,COD去除率92%。     

处理过的老龄垃圾渗滤液为阴极液的微生物燃料电池性能研究

处理过的老龄垃圾渗滤液与好氧污泥悬浊液的混合液按不同体积配比(0%、25%、50%、75%和100%),作为阴极液,构建生物阴极型微生物燃料电池(MFC),研究其产电特征以及对阳极底物和阴极液中污染物的处理效果。结果表明,处理过的老龄垃圾渗滤液作为阴极液时,MFC对化学需氧量(COD)和氨氮的去除率较其作为阳极液时分别提高2.27倍和42%。处理过的老龄垃圾渗滤液与好氧活性污泥悬浊液的混合液作为阴极液可提高MFC的产电性能和对污染物的去除效果。以体积比为75%的处理过的老龄垃圾渗滤液作为阴极液时,能显著提高MFC产电效果,输出电压和输出功率密度最大,分别为498 mV、295.2 mW/m~3,内阻最小为244Ω,阳极COD去除率最高为44.81%。     

MFCs处理养猪场废水及其产电性能的中试研究

文章开展了微生物燃料电池(Microbial Fuel Cells,MFCs)处理养猪场废水的中试研究。试验装置有效容积为305 L,设计水力停留时间(HRT)为24 h,考察该装置对养猪场废水的处理效果及其产电能力。结果表明:当反应器稳定运行后,出水COD保持在500 mg/L以下,出水恶臭明显减少;出水重金属全部指标均达到农田灌溉水质标准,但出水氨氮与总磷去除效果较差;外接1Ω电阻时,输出电压保持在400 mV以上,最大功率密度达到154.9 mW/m~2。     

Effect of electrode fabrication methods on the electrode performance for ethanol oxidation

Two palladium/carbon nanofibers modified glassy carbon electrodes, Pd/CNFs/GC-C and Pd/CNFs/GC-E, are fabricated by the conventional powder type method and by the electrophoretic deposition in conjunction with pulse electrodeposition method, respectively. Field emission scanning electron microscopy and high resolution transmission electron microscopy reveal that Pd particles are uniformly dispersed on the two electrodes and X-ray diffraction shows the average Pd particle size of the Pd/CNFs/GC-E electrode is slightly larger than that of the Pd/CNFs/GC-C electrode. Cyclic voltammetric analysis shows that the electrocatalytic activity of Pd/CNFs/GC-E electrode is better than that of Pd/CNFs/GC-C electrode for ethanol oxidation in alkaline media, although the latter has higher Pd loading than the former. This is believed to be due to the higher utilization of Pd catalyst on Pd/CNFs/GC-E electrode than on Pd/CNFs/GC-C electrode, which is confirmed by the electrochemically active surface area measurements. In addition, chronopotentiometric analysis shows the long-term operation stability of Pd/CNFs/GC-E electrode is better than that of Pd/CNFs/GC-C electrode.     

Status of the secondary lithium electrode

Over the past decade, several major advances have been made in improving the cycling efficiency of the secondary Li electrode. This review article summarizes the research leading up to these advances and describes “state-of-the-art” electrolytes for normal temperature, secondary Li batteries, as reported in the open literature. Remaining problems are identified and areas for additional research are suggested.     

单相电极盐浴炉熔盐电阻计算及电极尺寸设计

本文研究了单相马蹄形、平行板形(相对或同侧)电极盐浴炉熔盐电阻的计算及电极尺寸的设计方法。实践表明,文中的计算方法可满足工程要求。     

Modified equations for the performance of oxygen reduction reaction catalyst from rotating disk electrode to membrane electrode assembly

Kinds of electrocatalysts developed for the cathode of Polymer electrolyte membrane fuel cell (PEMFC) show more outstanding performance when loading on rotating disk electrode (RDE) than assembling in the membrane electrode assembly (MEA), and this phenomenon has not be explained quantitatively yet. Here we developed the Butler-Volmer equation further on the base of the detailed disassembly of the elemental reaction processes that occurring on the surface of the cathodic catalyst and in the MEA. These analytical equations quantifiably indicate how the catalyst's structural parameters and electrode's microstructural parameters to influence the performance of catalyst. Further analysis shows there may be more than one order of magnitude for the PEMFC's current density improvement when using the traditional catalyst like Pt/C, after optimizing the structure of catalytic layer. Meanwhile, the increasing hydrogen permeation not only lower the open-circuit voltage but also cause the whole polarization curve moving down, which means an attenuation of PEMFC's lifetime. These equations shown in this work are established on the strict deduction of mathematics and physics and will give the new guidance for evaluating and improving the performance of electrocatalysts when assembling in MEA.     

Compact dynamic hydrogen electrode unit as a reference electrode for PEMFCs

A compact and easy-handling design for the dynamic hydrogen electrode (DHE) was proposed. Before mounting in the cell, a unitized set was made by the hot-pressing of two 2 mm × 5 mm ionomer membranes, between which two PTFE-coated platinum wires were sandwiched. Before the hot-pressing, a small amount of paste composed of platinum black powder and an ionomer solution was dropped at the end of each wires. Prior to use in a PEMFC, a proper current value for the operation was found in an aqueous acid solution. Mounting of the DHE on a membrane electrode assembly (MEA) was done by local hot-pressing. The space for the mounting was only 2 mm in width between the gasket and edge of the gas diffusion electrode. The potential of the DHE fluctuated, but it was in the range of about 5 mV. A PEMFC with both the DHE and conventional RHE was operated, and the I–V performance of the PEMFC was measured. The potential difference between the conventional RHE and DHE was about 5 mV, which is due to the overpotential of the hydrogen evolution reaction at the DHE. Considering this difference, this DHE is available to monitor single electrode potentials.     

Influence of the morphology on the platinum electrode surface activity

Polycrystalline Pt electrodes with different surface characteristics were investigated by cyclic voltammetry (CV) in 0.5 M H₂SO₄. Plane electrodes showed a decrease in electrochemically active surface area while cycling in the hydrogen underpotential region (H_upd), in contrast, electrodes roughened by intensive pre-cycling exhibited a stable value for the electrochemically active surface.     

Enhancement of hydrogen evolution reaction by Pt nanopillar-array electrode in alkaline media and the effect of nanopillar length on the electrode efficiency

Pt nanopillar-array 3D electrodes with nanopillar length of 150, 450 and 900 nm and nanopillar density of ~10⁹ cm⁻² were fabricated. Their catalytic activity for hydrogen evolution reaction (HER) was evaluated by linear sweep voltammetry and electrochemical impedance spectroscopy. In comparison with straightly electrodeposited black Pt film and forged Pt sheet electrodes, the HER current density has been significantly improved by the nanopillar-array architecture. The overpotential of HER at current density of 10 mA cm-2 at 26 °C is as low as 78 mV, lower than the black Pt film of 107 mV and the Pt sheet of 174 mV. The improvement of HER is ascribed to the low charge transfer resistance of the 3D electrode and the high desorption capability of hydrogen bubbles at the nanotips. Interestingly, the nanopillar-array 3D electrode has an optimal nanopillar length for HER. The mechanisms for the optimal nanopillar length were investigated here.     

Research progress of the electrode materials for electrochemical capacitors

超级电容器是一种利用界面双电层储能或在电极材料表面及近表面发生快速可逆氧化还原反应而储能的装置,因其高比功率和长循环寿命等特点而具有广阔的应用前景,高性能电极材料是当前超级电容器研究的重点.本文简单介绍了超级电容器电极材料的分类,并对碳素材料,过渡金属氧化物,导电聚合物等三类超级电容器电极材料及其复合材料的研究进展进行了简单论述.     

铁合金炉的电极夹紧机构的设计

本文介绍铁合金炉气动电极夹紧机构的结构组成及工作原理。详细介绍气囊、气缸、弹簧及拉杆等的设计计算。