储氢材料的应用与发展

车用镍氢电池性能优良、安全可靠、技术成熟稳定,是混合动力车(HEV)比较理想的辅助动力。随着混合动力车技术的不断发展,动力电池用储氢合金将迎来一个黄金发展期。此外,随着燃料电池技术的日益成熟与发展,以氢气为燃料的电动汽车也将迅速发展起来,这就要求必须有安全高效的贮氢系统与之相匹配。传统的液态及高压气态贮氢方式由于成本、质量、体积大小以及安全性等因素限制,无法应用于车载贮氢系统。相比之下,金属氢化物作为一种新型的能源材料,具有贮氢密度高、安全高效及环境友好等优点,将成为未来车载燃料电池的氢载体。文章主要对近期Ni/MH电池用储氢合金的种类和发展以及高容量镁基储氢材料方面的研究工作做一些综述分析,以期为未来的研究工作提供参考。     

Advanced thermal spray technologies for applications in energy systems

Atmospheric plasma spraying technologies have been used to produce coatings for different applications in energy systems as gas turbines and solid oxide fuel cells (SOFCs). Thermal barrier coatings (TBCs) are widely used in gas turbines to protect structural parts from the combustion gases. Although they are in use since several decades there is still a large amount of research focused on a further improvement going on. Especially increased temperature capability, improved microstructures or optimized optical properties of the coatings will be described in the present paper. Atmospheric plasma spraying (APS) technology has also been used to manufacture different coatings for solid oxide fuel cell systems. These coatings include NiO/YSZ coatings for anodes, YSZ coatings for electrolytes and different functional coatings as Cr-evaporation layer on interconnects. Recent results on these different kinds of coatings will be shown. Performance data of SOFCs on metallic porous substrates will also be given.     

氢燃料电池中钛双极板研究进展

钛及钛合金密度低、比强度高且在酸性环境中耐蚀性优异,在氢燃料电池双极板中具有较高的应用价值。回顾了近年来氢燃料电池用钛双极板的研究进展,详述了钛双极板表面改性技术的研究成果,包括掺杂合金元素、钛表面涂覆金属基涂层(贵金属、金属碳/氮化物等)和碳基涂层(石墨、无定型碳等)。涂层结构组织的复合化和纳米化,有利于提升钛双极板的耐蚀性、导电性和疏水性,其对于提升氢燃料电池的性能及保证其运行的稳定性和耐久性具有重要作用。     

氧化物—空气半燃料电池用贮氢合金电极的烧结制备及其电化学特性

研究了应用在空气－氢化物半燃料电池上的制备配套金属氢化物厚型电极烧结技术，将贮氢合金与细镍粉和一定的添加剂形成浆料涂覆在泡沫镍基体，测试不同烧结参数对贮氢合金电极的电化学性能的影响，烧结电极合金的电化学活化特性和高倍率放电能力与传统的粘结式电极有较大的提高，为设计适合电动车用高能量密度空气－氢化物燃料电池，分别选用冲孔镍箔带，冲孔铜箔带和铜编织网作为集流体进行比较实验。结果表明，选定冲孔铜箔带是适宜于设计空气－氢化物燃料电池用厚型氢化物电极。     

Microstructured fuel processors for fuel-cell applications

Microstructured reactors are being developed at IMM for the processing of various fuels to provide hydrogen for mobile and portable fuel-cell systems. The key feature of the systems is the integrated-plate heat-exchanger technology, which allows for thermal integration of several functions in a single device. For example, steam reforming may be coupled with exothermic reactions in separate flow-paths of a heat exchanger. Catalyst coatings are also under development for numerous reactions, such as propane steam reforming, methanol steam reforming, catalytic combustion, water-gas shift, and preferential oxidation of carbon monoxide. These catalysts are being investigated in specially developed testing reactors. Reactors and complete fuel processors are being tested up to 5 kW power output of the corresponding fuel cell. This paper was presented at the ASM Materials Solutions Conference & Show held October 18–21, 2004 in Columbus, OH.     

Structuring of nanoporous nickel-based superalloy membranes via laser etching

Structures with a very fine and regular porosity enable inventions or further developments of a multitude of components like substrate applications in fuel cell technology or catalytic reaction spaces in chemical reactors. Here we show a novel method for structuring nanoporous metal membranes to generate one-component modules with multi-functionality. For this purpose a combination of the laser etching and electrochemical-etching techniques is applied to directional coarsened nickel-based superalloys.     

车载燃料电池用铂基催化剂的研究进展

能源危机和环境污染是车载燃料电池发展的主要驱动力。电催化剂的性能和成本是制约其实现商业化的关键因素之一。目前,车载燃料电池用催化剂主要是铂(Pt)基催化剂,文章对质子交换膜燃料电池、直接甲醇燃料电池和甲酸燃料电池三种车载燃料电池用铂基催化剂的研究进行综述,并对其存在的问题进行了分析和讨论。     

泡沫镍基合金材料制备及应用研究进展

泡沫镍合金是一种具有独特结构和性能的新型功能材料,重点阐述了多孔泡沫镍合金的制备方法和技术,并对各种方法的国内外发展现状进行了评述,分析和讨论了各种方法的优缺点。最后系统介绍了泡沫镍合金材料在高温过滤器、阻燃器、燃料电池载体材料、析氢电极等领域应用的优异性能,并展望其广阔的市场前景。     

直接甲醇燃料电池阳极催化剂载体的研究进展

阳极催化反应的反应动力学缓慢是限制直接甲醇燃料电池(DMFC)技术发展的主要原因之一,其中催化剂载体对阳极催化反应有重大影响,载体材料的选择对于决定催化剂乃至燃料电池的性能、效率、稳定性和成本都至关重要。基于对30多篇文献的分析,本文分类综述了用于DMFC碳基催化剂载体包括炭黑、介孔碳、碳纳米管(CNTs)、石墨烯和碳纤维纸,非碳基催化剂载体包括金属有机框架(MOF)、新型二维材料MXenes、钛基材料等材料的研究进展。     

Praxair’s dilute oxygen combustion technology for pyrometallurgical applications

Dilute oxygen combustion (DOC) technology uses separate high-velocity fuel and oxygen jets to generate strong in-furnace gas recirculation, producing combustion between the fuel and a highly diluted oxygen and furnace-gas mixture. These very low NOx oxy-fuel burners have been developed and commercially demonstrated in steel reheating furnaces. The burner design meets industry needs for increased productivity and lower operating costs with minimal capital expense and low maintenance. The performance of DOC technology has been measured under laboratory and industrial conditions encompassing both natural gas and coke oven gas firing, and a wide range of furnace temperatures and nitrogen levels that simulate air infiltration. This paper describes the results of the tests using natural gas as the fuel and lists potential applications for DOC technology in the non-ferrous metals industry. For more information, contact A.C. Deneys, Praxair, Inc., Applications Research and Development, 777 Old Saw Mill River Road, Tarrytown, New York 10591; e-mail Adrian_Deneys@Praxair.com.     

Degradation Characteristics of Elastomeric Gasket Materials in a Simulated PEM Fuel Cell Environment

Polymer electrolyte membrane (PEM) fuel cell stack requires gaskets and seals in each cell to keep the reactant gases (hydrogen and oxygen) within their respective regions. The stability of the gaskets/seals is critical to the operating life as well as the electrochemical performance of the fuel cell. The time-dependant chemical and mechanical degradation of two commercially available silicones-based elastomeric gasket materials in a simulated fuel cell environment was investigated in this work. Two temperatures based on actual fuel cell operation were selected and used in this study. Using optical microscopy, the topographical damage on the sample surface due to the acidic environment was revealed. Atomic adsorption spectrometer analysis shows that silicon, calcium, and magnesium were leached from the materials into the soaking solution. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) were employed to study the surface chemistry of the elastomeric gasket materials before and after exposure to the simulated fuel cell environment over time. The ATR-FTIR and XPS test results indicate that the surface chemistry changed significantly and the chemical degradation mechanism is de-crosslinking and chain scission in the backbone. The microindentation test results show that the mechanical properties of the silicone materials changed significantly after exposure to the simulated PEM fuel cell environment over time.     

碳材料的掺杂改性及其用于燃料电池催化剂的研究

开发掺杂改性的碳材料用作燃料电池的非贵金属氧还原催化剂已成为燃料电池领域的重要研究课题,相关研究对于降低燃料电池成本、促进燃料电池的商业化具有十分重要的意义。大量研究工作表明,对碳材料进行掺杂改性可以实现其形貌、微观结构、组成及其他表面物理化学性质的优化,从而得到具有较高催化活性、选择性和稳定性的氧还原催化剂。人们在这类催化剂的制备方法、性能优化和催化机理等方面进行了大量研究工作。综述了对碳纳米管、石墨烯、介孔碳、大孔碳、碳微球等碳材料进行掺杂改性的最新进展。并基于目前的研究结果,展望了掺杂碳材料作为燃料电池非贵金属氧还原催化剂的应用前景和未来的发展趋势。     

燃料电池型酒精传感器的制备

介绍了1种利用膜电极组件测试酒精含量的燃料电池型酒精传感器,该燃料电池以Nafion 115作电解质,Pt、Pd等贵金属作电催化剂。用酒精做燃料,空气中氧做氧化剂．只要环境气中存在酒精气氛,电池立即输出电信号。在一定的浓度范围内电池的输出电压变化值与酒精浓度成正比关系。     

变频燃油加油机系统节能与控制研究

针对普通燃油加油机泵送效率低和能耗大的问题,提出将变频技术引入加油机系统中。分析了变频燃油加油机的结构和原理,通过理论分析推导了系统数学模型。针对变频燃油加油机系统存在的超调量大、动态响应慢、稳态精度不足等问题,提出了一种模糊自适应PID控制策略,建立相应的数学仿真模型,并搭建变频泵送系统实验平台,进行了能耗测试。仿真和实验结果表明:采用模糊PID控制的变频控制系统超调量小、稳定性好,该方法对输入信号变化的响应具有更好的鲁棒性和快速性,显著改善了系统控制效果。随着电机频率的增大,燃油加油机的泵送效率先增大后减小,证明了加油机系统引入变频技术的必要性。与普通燃油加油机相比,采用模糊PID自适应控制的燃油加油机大大降低了系统能耗,节能率达43%以上,加注精度可控制在0. 2%内。     

焙烧炉烘炉启动新技术应用

针对焙烧炉烘炉启动传统方法中存在的燃耗高、启动炉室损害大等缺点,提出采用新型工艺技术方案,并成功应用于一34室焙烧炉的烘炉启动工作。结果表明,新技术不仅使整个烘炉启动时间由原计划的45天降低到30天,天然气消耗量降低了37.6%,并且只需一个启动炉室,对焙烧炉本体损害降到了最低。     

Surface technology should improve PEM fuel cell performance

Leading industrial nations are investing in hydrogen technology as energy storage solution with fuel cells as the main converter to electric energy. Improvements in the performance of the key components: electrode catalyst, bipolar plates and polymer electrolyte membrane are needed to reduce costs for mass-market introduction. Consequently, surface technology has an essential role in meeting the goals.     

Inert matrix fuel — A new challenge for material technology in the nuclear fuel cycle

An innovative nuclear fuel concept for the utilization as energy resources and for the incineration of excess Pu arisings as well as for an effective transmutation of minor actinides (MA's; Am, Np and Cm) is discussed from the aspect of material technology. Stabilized cubic phase ZrO₂ and other potential candidate materials for the Inert Matrix are compared in terms of the material properties and other behaviors such as the behavior against irradiation with the relevant information currently available. Strategies for the use of the Inert Matrix Fuel concept in various countries are discussed and compared for their options in nuclear fuel cycle technology. This article based on a presentation made in the “Symposium on Nuclear Materials and Fuel 2000” held at the Korea Atomic Energy Research Institute (KAERI), Taejon, Korea, August 24–25, 2000 under the auspices of the Ministry of Science and Technology (MOST).     

Ru-Ni-YSZ多维阳极在直接乙醇SOFC的应用研究

采用浸渍-自置换法,以Ru Cl3为添加剂,丙酮为表面活性剂,在阳极支撑SOFC的Ni-YSZ阳极上表面制备纳米Ru功能层,并制备Ru-Ni-YSZ||YSZ||Pd-Ag单电池。通过SEM,TEM,XRD对电极进行表征,发现Ru在Ni-YSZ阳极表面以及内部可以形成多维纳米花状催化层。通过测试不同沉积量和不同温度下纳米Ru层对单电池的电性能的影响。在750℃时,以乙醇为燃料,Ru沉积量为0.6%(质量分数)的燃料达到最高264 m W/cm~2。当Ru沉积量为0.4%时,燃料电池在700,750,800℃时,最大功率分别达到200、261和316 m W/cm2。在开路电压条件下,电池运行15h,没有出现下降和积碳现象。     

河钢塞尔维亚钢厂高炉煤气双蓄热加热炉的技术特点

介绍了河钢塞尔维亚斯梅带雷沃钢厂新建3~(#)双蓄热式加热炉的技术特点。其采用高炉煤气替代天然气,降低了燃料成本;通过合理的燃料配比及烟气反吹燃烧等技术的应用,解决了蓄热式加热炉NO_x和CO超标排放的问题;此外,该加热炉还采用了汽化冷却、均热段倾斜式炉底和排渣孔等技术,以及一级和二级控制技术,提高了加热炉的经济效益和操作便利性。     

PEM fuel cells: status and challenges for commercial stationary power applications

The past decade has seen tremendous advances in proton exchange membrane fuel cell (PEMFC) technology: However, there remain many challenges to bring commercially viable stationary PEMFC products to the market. This review, from a manufacturer's perspective, focuses on system reliability and materials compatibility and their strong impact on stack life and overall system durability. Statistical analysis is based on field data from more than 600 stationary PEMFC systems for both continuous and back-up power applications. Sealing materials and coolants are used to illustrate the approaches taken to evaluate materials compatibility studies.