配位氢化物储氢材料Mg（BH4）2的研究进展

Mg(BH4)2是一种新型配位氢化物储氢材料,因具有较高的质量储氢密度(14.8wt.%)和体积储氢密度(112g/L)而备受关注。本文系统概述了近年来有关Mg(BH4)2的诸多研究成果,主要包括Mg(BH4)2合成,晶体结构解析及其储氢性能的表征研究。在这些研究基础上,对该材料在储氢应用中可能涉及的动力学及热力学问题进行分析,同时预测该体系未来的研究方向和发展趋势。     

高容量储氢材料的研究进展

氢能是一种理想的二次能源.氢能开发和利用需要解决氢的制取、储存和利用3个问题,而氢的规模储运是现阶段氢能应用的瓶颈.氢的储存方法有高压气态储存、低温液态储存和固态储存等3种.固态储氢材料储氢是通过化学反应或物理吸附将氢气储存于固态材料中,其能量密度高且安全性好,被认为是最有发展前景的一种氖气储存方式.由轻元素构成的轻质高容量储氢材料,如硼氢化物、铝氢化物、氨摹氢化物等,理论储氢容量均达到5%(质量分数)以上,这为固态储氢材料与技术的突破带来了希望.新型储氢材料未来研究的重点将集中于高储氢容量、近室温操作、可控吸/放氢、长寿命的轻金属基氢化物材料与体系.     

高密度储氢材料研究进展

氢是一种清洁的燃料,氢能是未来有发展前景的新型能源之一.氢的储存是氢能现阶段开发和利用的瓶颈.氢的储存方法有高压气态储存、低温液态储存和固态储存等3种,其中高压气态储存或低温液态储存不能满足将来的储氢目标.固态储氢是通过化学或物理吸附将氢气储存于固态材料中,其能量密度高且安全性好,被认为是最有发展前景的一种氢气储存方式.高密度储氢材料由轻元素构成,包括铝氢化物、硼氢化物、氨基氢化物、氨硼烷等,理论储氢质量分数均达到5%以上.综述了高密度储氢材料的研究进展,认为高储氢容量、近室温操作、可控吸/放氢、长寿命的轻质氢化物材料有希望达到燃料电池和移动氢源应用的目标.     

镁基储氢材料研究现状

从镁基储氢材料体系、制备方法及其应用研究等方面对该类材料进行了综述,归纳分析了影响镁基储氢材料吸放氢性能的因素,明确了镁基储氢材料未来的研究方向。     

三氢化铝的结构及其储氢性能研究

近年来,三氢化铝作为一种新型的固态储氢材料,因其较高的储氢容量和较低的放氢温度,其在可移动氢源系统,特别是车载储氢燃料电池方面的应用研究愈加广泛。阐述了三氢化铝的晶体结构,对国内外在其储氢特性(分解脱氢热力学和动力学特性、可逆循环)和储氢改性方面(稳定化、去稳定化)的研究进展进行了综述,并展望了其未来发展趋势。     

核壳结构纳米镁基复合储氢材料研究进展

氢能的有效开发和应用主要需解决氢的安全、高效储运瓶颈问题。MgH_2具有高储氢容量、资源丰富以及成本低廉等优点,被认为是最具发展前途的一类储氢材料。但是,MgH_2较高吸放氢温度和较慢吸放氢速率限制了其实际应用。核壳结构纳米镁基储氢材料有助于材料储氢性能的改善,目前已取得了大量成果。本文针对国内外纳米镁基核壳结构储氢体系研究现状,归纳了该类储氢材料的制备方法,重点阐述和总结了其吸放氢热力学动力学性能、微观结构、物相变化,并对该领域的研究成果和方向进行了总结和展望,指出调控核壳结构镁基材料的纳米尺寸、添加高效纳米催化剂及其综合协同作用是镁基储氢材料领域未来的研究趋势和重要研究方向。     

新型芳香族多羧酸配体1,3,5-三(间苯二甲酸)的合成与表征

为了增加金属有机骨架材料对氢气的吸附势能叠加量以及得到配位不饱和的金属中心,从而提高材料对氢气的吸附焓,改善材料在常温下的储氢性能,通过SUZUKI偶联反应,设计合成了新型芳香多羧酸配体1,3,5-三(间苯二甲酸)。该新配体集中了合成NOTT-112和MOF-177的配体的特点。与合成NOTT-112的配体相比,新配体减少一个苯环的尺寸,将使聚合物材料的孔尺寸相应减小,增加对氢气的吸附势能叠加量。与合成MOF-177的配体相比,新配体的羧酸配位数增加1倍,将使聚合物中的晶体结构更加多样化。可以预测,用新配体合成的新型金属有机骨架材料可以兼顾NOTT-112及MOF-177的性能,对吸附储氢材料的研究开发具有重要意义。     

新型储氢材料的中子衍射研究

利用高灵敏度中子粉末衍射对新型储氢材料Li2NH,LiNH2,Li4BN3H10和BH3NH3的晶体结构进行了研究.通过对中子衍射数据的拟合分析得到了材料的晶格参数,原子占位和键长等数据.研究发现测量的氢原子占位结果与X-光衍射测量的结果有明显差别.结果表明储氢材料的氧释放温度与材料中的N-H或B-H键的键长成对应关系.通过将不同的储氢材料,例如LiBH4和LiNH2,进行复合改变材料中N-H和B-H氢键的强度,可以合成新的材料,有望达到储氢的目标.     

镁基储氢材料的研究进展与发展趋势

对近年来镁基储氢材料的研究开发概况、制备技术以及应用研究等方面进行了系统阐述,分析了影响镁基储氢材料储氢性能的主要因素,总结了采用机械合金化法、储氢合金组元部分替代、添加催化剂制成复合材料及表面改性等方法可以有效改善储氢性能,并对镁基储氢材料研究中存在的问题以及今后的发展方向进行了探讨与展望.     

金属氨硼烷及其衍生物高容量储氢材料研究进展

氨硼烷因其超高的储氢量和较好的动力学性能,成为了最具潜力的储氢材料之一。从合成方法、放氢特性、晶体结构和反应机制等方面,综述了金属氨硼烷及其衍生物的研究进展。     

金属合金及碳材料储氢的研究进展

论述了金属合金和碳材料的储氢机理、吸放氢量和动力学性能;探讨了活性金属Ni、Pd、Li和K对碳材料储氢的催化性能和金属Mg与多壁纳米碳管、碳纳米纤维、高比表面积活性炭、无烟煤和纳米石墨等碳材料复合储氢的性能及机理;指出了储氢材料应该向Li、Na、Mg、Al、B等轻元素和无烟煤、石墨等储量大、赋存广、成本低的碳材料方向发展.     

First principles calculations of H-storage in sorption materials

A review of various contributions of first principles calculations in the area of hydrogen storage, particularly for the carbon-based sorption materials, is presented. Carbon-based sorption materials are considered as promising hydrogen storage media due to their light weight and large surface area. Depending upon the hybridization state of carbon, these materials can bind the hydrogen via various mechanisms, including physisorption, Kubas and chemical bonding. While attractive binding energy range of Kubas bonding has led to design of several promising storage systems, in reality the experiments remain very few due to materials design challenges that are yet to be overcome. Finally, we will discuss the spillover process, which deals with the catalytic chemisorption of hydrogen, and arguably is the most promising approach for reversibly storing hydrogen under ambient conditions.     

储氢材料的发展概况

主要介绍了目前研究比较多的两系列储氢材料--金属合金系列和碳系列,特别是有关金属合金系列储氢材料的储氢原理、设计和合成以及表面修饰等方面的知识,同时对碳系列储氢材料的种类、合成等也做了简要的叙述,并提出储氢材料的最终发展方向将是走向复合型的储氢材料.     

Cover Picture: Nanotechnological Aspects in Materials for Hydrogen Storage (Adv. Eng. Mater. 6/2005)

The cover shows the schematic structure of an aluminum and magnesium containing hydrogen storage material. More about nanotechnological aspects in materials for hydrogen storage can be found in the article by M. Fichtner on page 443. A nanotechnological app#roach aims at making tailor‐made developments for storage materials by combining different scientific disciplines and focussing on processes on the microscale. The approach has already been successful in achieving major advances in the field of novel solid materials for hydrogen storage. However, further breakthroughs are necessary to reach the goal of storage systems for fuel cell‐driven, mobile applications.     

石墨烯及其聚合物复合材料在锂离子电池中的应用研究进展

石墨烯的出现为设计和构建新型功能复合材料提供了广阔的空间,文中详细综述了石墨烯及其聚合物复合材料在锂离子电池中的研究进展。石墨烯是一种极有发展潜力的负极材料,储锂性能受到结构特征、含氧官能团和杂质原子等多种因素影响,导致储锂行为和机理较为复杂。将具有储锂活性的聚合物与石墨烯复合作为正极材料,储锂性能受到聚合物氧化还原的可逆性和复合结构等因素影响。聚合物还作为晶格匹配剂和交联剂,有利于提高石墨烯与氧化物复合的结构稳定性。最后指出,聚合物种类和制备方法的选择是以改善储锂性能为原则,有针对性和预见性地设计和制备高性能锂离子电池电极材料。     

Methodology of materials discovery in complex metal hydrides using experimental and computational tools

We present a review of the experimental and theoretical methods used in the discovery of new metal–hydrogen materials systems for hydrogen storage applications. Rather than a comprehensive review of all new materials and methods used in the metal hydride community, we focus on a specific subset of successful methods utilizing theoretical crystal structure prediction methods, computational approaches for screening large numbers of compound classes, and medium-throughput experimental methods for the preparation of such materials. Monte Carlo techniques paired with a simplified empirical Hamiltonian provide crystal structure candidates that are refined using density functional theory. First-principle methods using high-quality structural candidates are further screened for an estimate of reaction energetics, decomposition enthalpies, and determination of reaction pathways. Experimental synthesis utilizes a compacted-pellet sintering technique under high-pressure hydrogen at elevated temperatures. Crystal structure determination follows from a combination of Rietveld refinements of diffraction patterns and first-principles computation of total energies and dynamical stability of competing structures. The methods presented within are general and applicable to a wide class of materials for energy storage.     

Hydrogen storage: The major technological barrier to the development of hydrogen fuel cell cars

In this paper, we review the current technology for the storage of hydrogen on board a fuel cell-propelled vehicle. Having outlined the technical specifications necessary to match the performance of hydrocarbon. fue1, we first outline the inherent difficulties with gas pressure and liquid hydrogen storage. We then outline the history of transition metal hydride storage, leading to the development of metal hydride batteries. A viable system, however, must involve lighter elements and be vacuum-tight. The first new system to get serious consideration is titanium-activated sodium alanate, followed by the lithium amide and borohydride systems that potentially overcome several of the disadvantages of alanates. Borohydrides can alternatively produce hydrogen by reaction with water in the presence of a catalyst but the product would have to be recycled via a chemical plant. Finally various possible ways of making magnesium hydride decompose and reform more readily are discussed. The alternative to lighter hydrides is the development of physisorption of molecular hydrogen on high surface area materials such as carbons, metal oxide frameworks, zeolites. Here the problem is that the surface binding energy is too low to work at anything above liquid nitrogen temperature. Recent investigations of the interaction mechanism are discussed which show that systems with stronger interactions will inevitably require a surface interaction that increases the molecular hydrogen-hydrogen distance.     

Mg／MmNi5—x（CoAlMn）x复合储氢合金的机械合金化制备

用高能球磨法制备了Ｍｇ／ＭｍＮｉ５－ｘ（ＣｏＡｌＭｎ）ｘ纳米晶复合储氢材料,通过对不同成分和球磨条件所得到的样品的组织结构进行Ｘ射线衍射,扫描电镜,能谱分析,获得了球磨参数对所制备的复合储氢合金组织结构的影响规律及所得组织的特点,结果表明,经过一定时间的球磨后的Ｍｇ／ＭｍＮｉ５－ｘ（ＣｏＡｌＭｎ）ｘ形成团粒组织,根据Ｘ射线衍射的结果估算了不同球磨条件及成分的复粉中的各相的晶粒尺寸其变化。     

机械合金化制备镁系储氢材料的研究进展

机械合金化法是新近发展起来的制备镁系储氢材料的较佳工艺.综述了国内外采用该法制备镁系储氢材料的研究进展情况,报道了机械合金化法制备MgH4、Mg2Ni、多元镁基储氢合金、非晶态镁系储氢合金及纳米复合镁系储氢材料的最新研究成果,总结认为,机械合金化可以显著改善镁系储氢材料的动力学性能和电化学性能,提高储氢量.