Characteristic Analysis of the Solid Oxide Fuel Cell with Proton Conducting Ceramic Electrolyte

An electrolyte model for the solid oxide fuel cell (SOFC) with proton conducting perovskite electrolyte is developed in this study, in which four types of charge carriers including proton, oxygen vacancy (oxide ion), free electron and electron hole are taken into consideration. The electrochemical process within the SOFC with hydrogen as the fuel is theoretically analyzed. With the present model, the effects of some parameters, such as the thickness of electrolyte, operating temperature and gas composition, on the ionic transport (or gas permeation) through the electrolyte and the electrical performance, i.e., the electromotive force (EMF) and internal resistance of the cell, are investigated in detail. The theoretical results are tested partly by comparing with the experimental data obtained from SrCe0.95M0.05O3-α, (M=Yb, Y) cells.

Sulfonated fluorinated multi-block copolymer hybrid containing sulfonated(poly ether ether ketone) and graphene oxide: A ternary hybrid membrane architecture for electrolyte applications in proton exchange membrane fuel cells

A ternary hybrid membrane architecture consisting of sulfonated fluorinated multi-block copolymer （SFMC）, sulfonated （poly ether ether ketone） （SPEEK） and I or 5 wt% graphene oxide （GO） was fabricated through a facile solution casting approach. The simple, but effective monomer sulfonation was performed for SFMC to create compact and rigid hydrophobic backbone structures, while conventional random sulfonation was carried-out for SPEEK. Hydrophilic-hydrophobic-hydrophilic structure of SFMC enhances the compatibility with SPEEK and GO and allows for an unprecedented approach to alter me- chanical strength and proton conductivity of ternary hybrid membrane, as verified from universal test machine （UTM） curves and alternating current （AC） impedance plots. The impact of GO integration on the morphology and roughness of hybrid membrane was scrutinized using field emission scanning electron microscope （FE-SEM） and atomic force microscope （AFM）. Ternary hybrid showed uniform intercalation of GO nanosheets throughout the entire surface of membrane with an increased surface roughness of 8.91 nm. The constructed ternary hybrid membrane revealed excellent water absorption, ion exchange capacity and gas barrier properties, while retaining reasonable dimensional stability. The well-optimized ternary hybrid membrane containing 5 wt% GO revealed a maximum proton conductivity of 111.9 mS/cm, which is higher by a factor of two-fold with respect to that of bare SFMC membrane. The maximum PEMFC power density of 528.07mW/cm2 was yielded by ternary hybrid membrane at a load current density of 1321.1 mA/cm2 when operating the cell at 70 ℃ under 100% relative humidity （RH）. In comparison, a maximum power density of only 182.06 mW/cm2 was exhibited by the bare SFMC membrane at a load current density of 455.56 mA/cm2 under same operating conditions.

Highly efficient vanadium redox flow batteries enabled by a trilayer polybenzimidazole membrane assembly

A novel polybenzimidazole(PBI)-based trilayer membrane assembly is developed for application in vanadium redox flow battery(VRFB).The membrane comprises a 1μm thin cross-linked poly[2,2′-(p-oxydiphenylene)−5,5′-bibenzimidazole](OPBI)sandwiched between two 20μm thick porous OPBI membranes(p-OPBI)without further lamination steps.The trilayer membrane demonstrates exceptional properties,such as high conductivity and low area-specific resistance(ASR)of 51 mS cm−1 and 81mΩcm^(2),respectively.Contact with vanadium electrolyte increases the ASR of trilayer membrane only to 158mΩcm^(2),while that of Nafion is 193mΩcm^(2).VO^(2+)permeability is 2.73×10^(-9) cm^(2) min^(−1),about 150 times lower than that of Nafion NR212.In addition,the membrane has high mechanical strength and high chemical stability against VO^(2+).In VRFB,the combination of low resistance and low vanadium permeability results in excellent performance,revealing high Coulombic efficiency(>99%),high energy efficiency(EE;90.8%at current density of 80mA cm^(−2)),and long-term durability.The EE is one of the best reported to date.

核-壳结构ZnO@CuO光阳极的制备及其光电性能研究

ZnO是钙钛矿太阳电池(PSCs)电子传输层(ETL)的优良材料,但ZnO与钙钛矿吸收层界面有很大的热不稳定性,从而导致该界面严重的电荷复合。文章采用水热法在FTO导电玻璃上制备出具有良好取向性的ZnO纳米棒阵列(NAs)。通过调控电化学沉积时间,在ZnO NAs上沉积一层CuO纳米颗粒,获得ZnO@CuO纳米复合材料薄膜。利用场发射扫描电镜(FESEM)、X射线衍射(XRD)对复合薄膜的形貌和物相进行了观察和分析。通过紫外-可见光漫反射(UV-Vis DRS)和瞬态荧光光谱(PL)对其光学性能进行了测定。结果表明,制备的ZnO NAs阵列均匀且垂直度较好,直径约为120 nm;通过电化学沉积CuO纳米颗粒(尺寸为34~44 nm)后,复合薄膜的可见光吸收能力增强,载流子分离效率提高;在电化学沉积时间为40 s时,所得到的ZnO@CuO NAs的光电流密度最高,约为ZnO NAs的3.37倍,表现出良好的光电转换性能。

《氢燃料电池动力船舶技术与检验暂行规则》部分条款解读

为促进业界对《氢燃料电池动力船舶技术与检验暂行规则》的准确理解和快速掌握,通过对比研究、案例分析、文献阅读等方法,分析《规则》出台的背景和意义,对其中的船舶布置、轮机、电气设备、控制监测与安全系统、消防、氢燃料储存和氢燃料加注等内容进行解读。《规则》的制定确保了氢燃料电池动力船舶符合安全和环保技术标准,标志着国内氢燃料电池动力船舶将正式进入工程化应用阶段。

Study of engineering electronic structure modulated non-noble metal oxides for scaled-up alkaline blend seawater splitting

Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a significant impact on hydrogen commercialization.Herein,we prepared energy-efficient,scalable,and engineering electronic structure modulated Mn-Ni bimetal oxides(Mn_(0.25)Ni_(0.75)O)through simple hydrothermal followed by calcination method.As-optimized Mn_(0.25)Ni_(0.75)O displayed enhanced oxygen and hydrogen evolution reaction(OER and HER)performance with overpotentials of 266 and115 mV at current densities of 10 mA cm^(-2)in alkaline KOH added seawater electrolyte solution.Additionally,Mn-Ni oxide catalytic benefits were attributed to the calculated electronic configurations and Gibbs free energy for OER,and HER values were estimated using first principles calculations.In real-time practical application,we mimicked industrial operating conditions with modified seawater electrolysis using Mn_(0.25)Ni_(0.75)O‖Mn_(0.25)Ni_(0.75)O under various temperature conditions,which performs superior to the commercial IrO_(2)‖Pt-C couple.These findings demonstrate an inexpensive and facile technique for feasible large-scale hydrogen production.

片层WC/C的原位合成及其在甲醇氧化中的应用

以片层二硫化钨(WS2)为前驱体,氯化钠(Na Cl)为介质,CO为气体碳源,采用程序升温法一步合成片层碳化钨/碳复合材料(WC/C)。通过X射线衍射(XRD),X射线近边吸收谱(XANES)和扫描电镜(SEM)等一系列手段对样品的化学组成、形貌、结构等进行表征。研究发现,在高温渗碳过程中,不仅利用WS2的片层结构和Na Cl的锚定作用合成了具有薄层孔洞的WC,而且Na Cl和WS2金属面对碳膜生长的催化作用使WC表面覆有原位生长的碳膜,为电子传输提供了有效通道。将该材料作为载体材料进行电化学性能测试,结果表明:负载少量Pt后制得的Pt/WC/C电催化剂,在甲醇氧化反应(MOR)中表现出良好的电催化活性、稳定性及优异的抗CO中毒能力。

基于FMECA方法的车用燃料电池发动机风险评估

在新能源汽车燃料电池发动机的产品开发过程中,对燃料电池发动机开展有效的风险评估对产品可靠性提升具有重要作用。今借助于失效模式影响及严重度分析(FMECA)方法对燃料电池发动机进行了风险评估。以某型燃料电池发动机样机为例,建立因素集、因素水平集、模糊因素水平评价矩阵、影响因素权重集等评估流程,利用模糊数学工具将FMECA的评价指标予以量化替代传统定性分析,避免了主观评价方法的随意性。运算得到一级模糊综合评价和综合危害等级,对该发动机9种典型失效模式的严重度评估和排序。分析结果与工程实践有较好的一致性,表明FMECA是一种适合燃料电池发动机可靠性开发过程中的风险评估方法。

Electrochemical determination of the degree of atomic surface roughness in Pt-Ni alloy nanocatalysts for oxygen reduction reaction

Pt-Ni alloy nanocrystals with Pt-enriched shells were prepared by selective etching of surface Ni using sulfuric acid and hydroquinone.The changes in the electronic and geometric structure of the alloy nanoparticles at the surface were elucidated from the electrochemical surface area,the potential of zero total charge(PZTC),and relative surface roughness,which were determined from CO-and CO_(2)-displacement experiments before and after 3000 potential cycles under oxygen reduction reaction conditions.While the highest activity and durability were achieved in hydroquinone-treated Pt–Ni,sulfuric acidtreated one showed the lower activity and durability despite its higher surface Pt concentration and alloying level.Both PZTC and QCO_(2)/QCO ratio(desorption charge of reductively adsorbed CO_(2) normalized by COad-stripping charge)depend on surface roughness.In particular,QCO_(2)/QCO ratio change better reflects the roughness on an atomic scale,and PZTC is also affected by the electronic modification of Pt atoms in surface layers.In this study,a comparative study is presented to find a relationship between surface structure and electrochemical properties,which reveals that surface roughness plays a critical role to improve the electrochemical performance of Pt-Ni alloy catalysts with Pt-rich surfaces.

Modeling of a SrCe_(0.95)Yb_(0.05)O_3-αHollow Fibre Membrane Reactor for Methane Coupling

Proton-hole mixed conductor, SrCeo.95Yb0.05O3-α(SCYb), has the potential to be used as a membrane for dehydrogenation reactions such as methane coupling due to its high C2-selectivity and its simplicity for fabricating reactor systems. In addition, the mixed conducting membrane in the hollow fibre geometry is capable of providing high surface area per unit volume. In this study, mechanism of methane coupling reaction on the SCYb membrane was proposed and the kinetic parameters were obtained by regression of experimental data. A mathematical model describing the methane coupling in the SCYb hollow fibre membrane reactor was also developed. With this mathematical model, various operating conditions such as the operation mode, operation pressure and feed concentrations affecting performance of the reactor were investigated. The simulation results show that the cocurrent flow in the reactor exhibits higher conversion of methane and higher yield of ethylene compared to the countercurrent flow. In order to achieve the highest C2 yield, especially of ethylene, pure methane should be used as feed and the operating pressure be 300 kPa. Air can be used as the source of oxygen for the reaction and its optimum feed velocity is twice of the methane feed velocity. The air pressure in the lumen side should be kept the same as or slightly lower than the pressure of shell side.

Effect of nanoclay on properties of porous PVdF membranes

The main requirements for battery separators are high porosity which can serve pathways of lithium ion and space for gel electrolytes to impregnate in a membrane and mechanical strength to allow easy handling for battery assembly. Generally, it appears the trade-off relationship between the porosity and mechanical strength of the membrane. PVdF composite membranes containing nano-size clays were used to improve the mechanical strength of the membrane without affecting the membrane porosity. The composite membranes were prepared by phase inversion method controlling the membrane preparation conditions such as retention time. The resultant membranes show increased mechanical properties with similar membrane porosity around 80 % compared to the pristine PVdF membrane. Incorporation of nonoclay can be considered as an effective method to improve the mechanica! strength in porous membrane supports, especially in a separator.

燃料电池和锂电池在船用领域的对比分析

本文首先比较燃料电池和锂电池的技术特点,然后以功率范围120~1200 kW,储能范围1~10 MWh的船用燃料电池和锂电池系统为对象,对比分析其重量、体积和价格,最后针对大功率、高储能的船型提出燃料电池和锂电池混合的动力方案。

质子交换膜燃料电池密封材料研究概述

相较于膜电极和双极板而言,密封材料是当前质子交换膜燃料电池研究领域被忽视被研究的对象。密封材料虽不参与电池电化学反应,但也是决定电池关键因素之一,其性能好坏直接影响电池发电效率和使用寿命。本文主要介绍了PEMFC密封材料的种类和技术指标要求,并综述了密封材料国内外研究现状。

PEM燃料电池稳定运行的工作条件分析

质子交换膜燃料电池持续稳定运行的理想工作条件是保持质子交换膜聚合物电解质的充分水合,阴极与阳极多余的水分及时的排出,保持电化学反应的水热平衡,本文对质子交换膜燃料电池的水热平衡进行了分析计算,提出通过选取燃料电池的最佳工作条件参数保障燃料电池的持续稳定运行。表明通过温度、压力、湿度、过量系数的选取,可确定燃料电池的最佳工作状态。

Synthesis, characterization and electrocatalytic studies of palladium–manganese oxyhydroxide nanocomposite towards direct ethylene glycol fuel cell

The palladium nanoparticle grafted manganese oxyhydroxide nanorod(MON) electrocatalyst has been synthesized and tested for the electrooxidation of ethylene glycol(EG) in an alkaline medium. The MON was prepared using the hydrothermal method and the Pd nanoparticles were coated on the MON using an in situ reduction method. The nanocatalyst thus prepared was characterized by powder X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy and electrochemical methods. The microscopic studies confirm the formation of MON and reveal that the Pd nanoparticles were grafted uniformly on the MON. In the voltammetric studies, the Pd/MON catalyst exhibited a six-fold improved peak current for ethylene glycol electrooxidation compared with the C/Pd. The EG electrooxidation reaction performances of the Pd/MON nanocatalyst in the alkaline solutions containing different quantities of EG were tested through cyclic voltammetry. The catalytic removal of the poisonous intermediates formed during electrooxidation of EG was explained. The present study shows that MON can act as an active support for the Pd nanocatalyst.

几种储氢技术在氢燃料电池船舶应用的对比分析

本文以氢燃料动力船舶用储制氢装置为研究对象,针对有机液体储氢、甲醇重整制氢、金属水解制氢和合金储氢四种具有发展潜力的储制氢技术,介绍其储制氢基本原理,归纳技术特点,并开展对比分析,最后针对船舶应用提出适用性建议,为船用燃料电池领域储氢技术提供参考。

利用TRIZ创新方法解决燃料电池电堆水淹问题

本文利用TRIZ创新方法解决燃料电池电堆水淹问题,通过冲突分析和物质-场分析求解,获得九个解决方案,针对解决方案进行可行解的失效分析,最终确定三种组合解,并通过样机或试验证明有效性。

船舶燃料电池系统可靠性分配与预计

本文以自主研发的船舶燃料电池系统为对象,建立其基本可靠性模型和任务可靠性模型,然后针对具体的可靠性定量指标进行可靠性分配获得各组成设备的可靠性参数,为燃料电池系统各组件的设计和选型提供可靠性指标参考,最后初步开展了可靠性预计分析。

燃料电池模块辅助单元试验结果与分析

本文介绍了一种燃料电池辅助单元组成。通过耐压测试、冷却水路极限测试、气路极限测试以及燃料电池模块耐久性测试来具体对燃料电池模块辅助单元进行研究,并针对耐久性试验中的具体故障进行了分析和处理。试验结果表明:在燃料电池模块辅助单元设计中,针对氢气泄露需按安全规范做特殊设计;关键参数的极限能力需设置上下限和自保流程。