Molecular and Atomic Hydrogen in Pillared Layered Materials: Towards Tuneable Hydrogen Storage

在这个下一代设施用户学生的申请中，我们将使用中子散射来研究两个原型柱状层状系统中的氢：石墨插层体和云母粘土。在这些材料中，我们可以调整层电荷和通道间距来优化氢的吸收，因此它们具有实用和基本的意义。清洁能源是一个热门话题，这将使我们更容易招募到高素质的学生。具体来说，为了实现氢经济，有几个技术挑战需要克服，其中许多与用于储存氢本身的材料有关。所需的性能指标已由美国能源部制定，包括氢的重量百分比和体积密度、氢的吸收/释放动力学、成本、寿命和安全性。目前有各种不同的技术正在研究中，但目前还没有材料达到2005年的目标。我们相信，在柱状石墨和粘土中，我们已经确定了一类能够满足这一需求的材料，而且便宜且环保（可回收）。此外，通过控制层间距、插层剂的浓度和类型、表面电荷和纳米级结构，它们的吸氢性能可高度调节。在基础层面上，该项目还将使学生深入了解H2的分子动力学和量子离域，以及由H2解离驱动的效应，包括KC8等材料的神秘重新定位。在诸如蛭石和云母之类的高电荷粘土中，H2的共插层尚未被研究，但我们希望学生会发现这些材料是富含阳离子的带电氧化物的优秀范例，具有可控的廊间距和吸收性能，远远优于沸石等材料。所有这些研究都将充分利用STFC的中子散射设施，特别是在ISIS脉冲源上，使用各种衍射和光谱仪器来开发独特的中子-质子散射，并为学生提供丰富的培训经验。

In this request for a Next Generation Facilities User studentship, we will use neutron scattering to study hydrogen in two prototypical pillared layered systems: graphite intercalates and mica clays. In these materials we can tune the layer charge and gallery spacing to optimise the uptake of hydrogen, and they are therefore of both practical and fundamental significance. Clean energy is a highly topical issue, and this will make it much easier for us to recruit a high-quality student. Specifically, for the hydrogen economy to be practical there are a several technological challenges to be overcome, many of which are associated with the materials used to store the hydrogen itself. The required performance targets have been codified by the US Department of Energy, and include the weight percent and volumetric density of hydrogen, the kinetics of its uptake/release, cost, lifetime and safety. At the moment there are various different technologies that are being investigated, but currently no material meets even the 2005 goals. We believe that in pillared graphite and clays we have identified a class of material that will be able to satisfy this need, and are also cheap and environmentally friendly (recyclable). Furthermore, their hydrogen absorption properties are highly tuneable via control of the interlayer spacing, the concentration and type of intercalant, the surface charge, and nano-scale texture. At a fundamental level, the project will also give the student insight into the molecular dynamics and quantum delocalisation of H2, and effects which are driven by H2-dissociation including the mysterious restaging of materials like KC8. In high charge clays such as vermiculite and mica, the co-intercalation of H2 is as yet unstudied, but we expect that the student will find that these materials are excellent exemplars of cation-rich charged oxides, with controllable gallery spacings and uptake properties far superior to materials such as zeolites. All of this research will make excellent use of the STFC's Neutron Scattering Facilities, at the ISIS Pulsed Source in particular, using a variety of diffraction and spectroscopy instruments to exploit the unique neutron-proton scattering, and providing a rich training experience for the student.