机械合金化Mg/MmNi5-x(CoAlMn)x复合储氢合金的组织结构与吸氢特性

运用Ｘ射线衍射、扫描电及粒度分析等方法表征了机械合金化制备Ｍｇ／ＭｎＮｉ５－ｘ（ＣｏＡｌＭｎ）ｘ复合储氢合金的结构,通过ＰＣＴ曲线研究了基储氢性能。结果表明,在适当的球磨条件下能够获得纳米晶结构的Ｍｇ／ＭｎＮｉ５－ｘ（ＣｏＡｌＭｎ）ｘ复合储氢合金,ＭｍＮｉ５－ｘ（ＣｏＡｌＭｎ）ｘ合金相彘,复合储氢合金的活化性能及储氢量有明显提高。此外,还考察了Ｍｇ含量对复合储氢合金的组织结构及储氢性能的影响。     

Mg-RE-Ni系镁基储氢材料的特性与制备

镁基储氢材料因具有理论可逆储氢容量高和价格低廉的优点,成为很有应用前景的固态储氢材料。本文综述了近年来Mg-RE-Ni系镁基储氢材料的研究进展,重点阐述了Mg-RE-Ni合金的物相组成、合金显微结构对该材料储氢性能的影响,介绍了该类合金储氢材料的制备方法：反应球磨法、氢化燃烧法与机械球磨法结合（HCS＋MM）、可控制的...     

我国金属氢化物化学研究

综述了我国金属氢化物化学的发展。我国是从５０年代中期开始研究离子型金属氢化物的合成、性能和应用的,发展了一些合成方法,获得了多项中国专利。储氢合金的化学研究是７０年代中期开始的。在储氢合金的化学合成、吸放氢热力学与动力学、储氢合金氢化催化和电化学方面都有较深入的研究,特别是储氢电极合金电化学及其在Ｎｉ／ＭＨ可逆电池中的应用研究,在国家８６３计划强有力的支持下,某些方面进入了国际先进行列。     

我国金属氢化物化学研究

综述了我国金属氢化物化学的发展。我国是从50年代中期开始研究离子型金属氢化物的合成、性能和应用的,发展了一些合成方法,获得了多项中国专利。储氢合金的化学研究是70年代中期开始的。在储氢合金的化学合成、吸放氢热力学与动力学、储氢合金氢化催化和电化学方面都有较深入的研究,特别是储氢电极合金电化学及其在Ni/MH可逆电池中的应用研究,在国家863计划强有力的支持下,某些方面进入了国际先进行列。     

稀土对LaNi3.5Co0.8Mn0.4Al0.3合金电化学及储氢特性的影响

研究了以Ｃｅ,Ｎｄ和Ｐｒ部分替代ＬａＮｉ３．５Ｃｏ０．８Ｍｎ０．４Ａｌ０．３中的Ｌａ后对合金电化学及储氢特性的影响。稀土含量的变化明显改变合金的电化学及储氢特性。随着Ｎｄ含量的增加,合金的放电容量降低。     

镁基储氢材料研究新进展

综述了近几年镁基储氢材料研究的最新进展，总结了目前改善镁基储氢材料性能所用的主要方法，例如反应机械合金化、氢化燃烧合成、掺杂催化元素、制备复合材料、组元替代等。指出采用反应机械合金化法、储氢合金组元调整以及添加催化剂是改善性能最有效的途径。     

稀土对LaNi_(3.5)Co_(0.8)Mn_(O.4)Al_(0.3)合金电化学及储氢特性的影响

研究了以Ce,Nd和Pr部分替代LaNi(3．5)Co(0.8)Mn(0.4)Al(0.3)中的La后对合金电化学及储氢特性的影响。稀土含量的变化明显改变合金的电化学及储氢特性。Pr对合金的电化学性能影响小于Ce。Ce使合金的放电容量降低,并升高合金的氢分解压。随着Nd含量的增加,合金的放电容量降低。     

《化学通报》网络版2003年第8期论文摘要

[W 0 5 7]元素取代法改善镁基储氢合金性能的研究进展TheDevelopmentofImprovingontheCharacteristicsofMagnesiumHydrogenStorageAlloysbyMeansofElementsSubstitution袁华堂　冯　艳 　宋赫男　王一菁 (南开大学新能源材料化学研究所　南开 天津大学联合研究院　天津　3 0 0 0 71 )镁基储氢合金的优点是储氢能力高、价格低、储量丰富。但是由于其在动力学和热力学以及抗腐蚀性方面存在不足 ,所以需要对其进行性能的改善。本文全面介绍了元素取代法对改善镁基合金性能的研究进展。Theadvantageofmagnesium basedhydrogenstorageall…     

Ti0.10Zr0.15V0.35Cr0.10Ni0.30+5wt% LaNi5复合储氢合金的电化学性能与协同效应

为了改善钛钒基固溶体合金的电化学性能,利用两步电弧熔炼法制备复合储氢合金Ti0.10Zr0.15V0.35Cr0.10Ni0.30+5wt%LaNi5,X-射线衍射(XRD)和场发射扫描电镜-能谱(FESEM-EDS)显示:复合储氢合金的主相是体心立方结构的钒基固溶体相和六方结构的C14 Laves相,复合过程中生成了第二相。电化学测试结果表明:复合合金电极的P-C-T特征、活化性能、最大放电容量、循环稳定性、低温放电性能和动力学特性均较母体合金有显著改善。复合合金电极的活化周期数为5,最大放电容量为353.9 mAh.g-1,233 K时低温放电能力为50.26%。该复合合金电极的最大储氢容量、平台压、电荷转移电阻和交换电流密度均存在协同效应;在任意循环、在高/低温下以及在高倍率放电过程中,该复合合金电极的放电容量均存在协同效应。     

镁基储氢合金的表面处理和表面催化

表面处理作为储氢合金性能改善的有效手段，近年来得到了很好的发展和应用，本文简要介绍了镁基储氢合金表面处理的主要方法及其对合金性能的影响。     

Exploring the structural,mechanical and thermodynamic properties of Ti-V solid solutions

Although Ti-V based high-temperature alloys are used in aerospace engine, rocket engine and hot sections, the structure and mechanical properties of Ti-V alloys remains controversy. To explore the correlation between structural and mechanical properties, we apply employed the DFT method to study the phases stability, mechanical and thermodynamic properties of Ti-V solid solution. Two Ti-V solid solutions: Ti(V)_ss solid solution and V(Ti)_ss solid solution are discussed. Two Ti-V solid solutions are thermodynamic stability. In particular, the Ti-V solid solution prefers to form V(Ti)_ss solid solution, in while the V(Ti)_ss solid solution remains cubic structure. Furthermore, the Ti(V)_ss solid solution is a mechanical instability. However, the V(Ti)_ss solid solution is a mechanical stability. Here, the bulk modulus, shear modulus and Young's modulus of V(Ti)_ss solid solution are 136.9, 23.5 and 66.7 GPa. In particular, the bulk modulus of V(Ti)_ss solid solution is higher than the bulk modulus of the pure Ti. In addition, the V(Ti)_ss solid solution shows better ductility compared to the pure Ti and V. Naturally, the stability and mechanical properties of V(Ti) solid solution is related to the Ti-V metallic bond because of the localized hybridization between the Ti(3d) and V(3d).     

缺陷对混合稀土贮氢合金性能的影响

贮氢合金是一种重要的功能材料。在多种贮氢合金中,AB~5型稀土系贮氢合金的应用最为广泛。本文用正电子湮没技术(PAT)对AB~5型混合稀土贮氢合金的缺陷进行了研究,并结合X射线衍射(XRD)测试、循环伏安(CV)测试以及合金容量的测定,对合金的结构及性能进行了研究。结果表明,合金微观缺陷的存在能大幅度提高金的性能。     

Problem of hydrogen storage and prospective uses of hydrides for hydrogen accumulation

Merits and demerits of existing methods of hydrogen storage are discussed. Special attention is given a metal hydride technology based on the ability of metals, intermetallic compounds, and alloys for reversible reaction with hydrogen. It is noted that the basic advantages of metal hydrides are a high volumetric hydrogen content, operational safety, technological flexibility, and low power inputs on hydrogen absorption and desorption.     

纳米镁储氢材料吸放氢动力学性能的研究进展

综述近十年来国内外有关纳米镁储氢材料吸放氢动力学的研究现状和发展趋势.众多研究表明,应用高能球磨法制备纳米镁复合储氢材料,并以过渡金属氧化物为催化剂,或者用ABx型储氢合金与镁复合,都能显著改善镁的吸放氢动力学性能.     

Mg-based nanocomposites with high capacity and fast kinetics for hydrogen storage

Magnesium and its alloys have shown a great potential in effective hydrogen storage due to their advantages of high volumetric/gravimetric hydrogen storage capacity and low cost. However, the use of these materials in fuel cells for automotive applications at the present time is limited by high hydrogenation temperature and sluggish sorption kinetics. This paper presents the recent results of design and development of magnesium-based nanocomposites demonstrating the catalytic effects of carbon nanotubes and transition metals on hydrogen adsorption in these materials. The results are promising for the application of magnesium materials for hydrogen storage, with significantly reduced absorption temperatures and enhanced ab/desorption kinetics. High level Density Functional Theory calculations support the analysis of the hydrogenation mechanisms by revealing the detailed atomic and molecular interactions that underpin the catalytic roles of incorporated carbon and titanium, providing clear guidance for further design and development of such materials with better hydrogen storage properties.     

Chemical-clathrate hybrid hydrogen storage: storage in both guest and host

Hydrogen storage from two independent sources of the same material represents a novel approach to the hydrogen storage problem, yielding storage capacities greater than either of the individual constituents. Here we report a novel hydrogen storage scheme in which recoverable hydrogen is stored molecularly within clathrate cavities as well as chemically in the clathrate host material. X-ray diffraction and Raman spectroscopic measurements confirm the formation of beta-hydroquinone (beta-HQ) clathrate with molecular hydrogen. Hydrogen within the beta-HQ clathrate vibrates at considerably lower frequency than hydrogen in the free gaseous phase and rotates nondegenerately with splitting comparable to the rotational constant. Compared with water-based clathrate hydrate phases, the beta-HQ+H2 clathrate shows remarkable stability over a range of p-T conditions. Subsequent to clathrate decomposition, the host HQ was used to directly power a PEM fuel cell. With one H2 molecule per cavity, 0.61 wt % hydrogen may be stored in the beta-HQ clathrate cavities. When this amount is combined with complete dehydrogenation of the host hydroxyl hydrogens, the maximum hydrogen storage capacity increases nearly 300% to 2.43 wt %.