New Adsorbents for Hydrogen Storage

CBET-0753008阳氢储存是通往未来“氢经济”的关键缺失环节。氢可以储存在压缩的储罐中，以液化的形式储存，也可以储存在装满吸收材料的压缩储罐中。最有前途的技术是吸附剂方法。吸附方法包括金属氢化物和吸附剂。对于交通应用，美国能源部设定了6.5wt%和62公斤氢气/立方米作为常温车载储氢的目标。压力没有具体说明，但100atm一直是研究的名义压力。作为参考，以燃料电池为动力的紧凑型乘用车，400公里的行驶里程需要4公斤氢气。移动应用的其他例子是存储便携式电子产品，如笔记本电脑和由燃料电池供电的手机，以及非汽车交通应用，如摩托车。开发新的吸氢剂用于常温储氢是一个最具挑战性的问题。使用氢溢出方法，通过一种简单的桥梁构建技术(用于促进溢出过程)，我们最近制备了在所有已知的吸着剂中，在环境温度下获得了迄今为止最高的可重复性(即由能源部指定的验证实验室)存储量的吸着剂。最近的实验和其他实验室的理论研究表明，通过碳中的硼取代或氮取代，可以显著增加氢和氢与碳之间的相互作用，从而增加存储容量。这项研究的目的是开发B-和N-取代碳材料用于移动和固定用途的储氢，以及对用于储氢的B-和N-取代碳的氢溢出现象有一个基本的了解。我们的工作将从合成高比表面积的B-和N-取代碳开始。我们的方法将包括在B-和N-取代碳上直接掺杂金属(用于氢解离成氢原子)，以及通过使用我们的桥接技术来进一步增加溢出存储。通过使用一些技术，包括使用氘(D)同位素示踪剂来跟踪溢出的动力学和机制，将对溢出现象有一个基本的了解。本工作开发的新型脱硫剂既适用于移动电源，也适用于固定电源。这个项目将包括各种研究生和本科生的积极参与。学生们将在全国会议和出版物上积极传播这些发现和发现。这项研究将带来一种新的储氢技术，这是实现未来“氢经济”的关键。本工作开发的新型脱硫剂既适用于移动电源，也适用于固定电源。此外，在这项工作中开发的吸附剂可以很容易地转移到工业应用中。此外，这项工作还将对氢溢出和反向溢出现象有一个基本的了解。

CBET-0753008YangHydrogen storage is the crucially missing link to a future "hydrogen economy." Hydrogen can be stored in compressed tanks, in liquefied form, and in compressed tanks filled with sorbent materials. The most promising technique is the sorbent approach. The sorbent approach includes metal hydrides and adsorbents. For transportation applications, the U. S. Department of Energy has set 6.5 wt% and 62 kg H2/m3 as the targets for on-board hydrogen storage at ambient temperature. The pressure is not specified, but 100 atm has been a nominal pressure for research. As a reference, for a compact passenger vehicle powered by fuel cell, 4 kg H2 is needed for a driving range of 400 km. Other examples for mobile applications are storage for portable electronics such as laptop computers and cell phones that are powered by fuel cells, as well as for non-automobile transportation applications such as motorcycles.To develop new adsorbents for hydrogen storage at ambient temperature is a most challenging problem. Using the hydrogen spillover approach, via a simple bridging building technique (for facilitating the spillover process), we have recently prepared sorbents that have achieved by far the highest reproducible (i.e., by the DOE-designated validation lab) storage amounts at the ambient temperature among all known sorbents. Recent experiments and theoretical studies from other laboratories have shown that the interactions between both H2 and H with carbon can be substantially increased by boron-substitution or nitrogen-substitution in the carbon, leading to increased storage capacities. This research is aimed at developing B- and N-substituted carbon materials for hydrogen storage for both mobile and stationary applications, as well as for obtaining a fundamental understanding of the hydrogen spillover phenomenon on B- and N-substituted carbons for hydrogen storage. Our work will begin with synthesis of B- and N-substituted carbons with high surface areas. Our approach will include both direct doping of metals (for hydrogen dissociation into hydrogen atoms) on the B- and N-substituted carbon, and by using our bridging technique to further increase the spillover storage. A fundamental understanding of the spillover phenomenon will be obtained by using a number of techniques, including the use of deuterium (D) isotope tracer for following the kinetics and mechanism of spillover. The new sorbents developed in this work should be applicable for both mobile and stationary power sources. This project will involve active participation of a diversity of graduate as well as undergraduate students. The students will be active in disseminating the findings and discoveries at national meetings and through publications. The research will lead to a new technology for hydrogen storage, which is crucially needed for realizing a future "hydrogen economy." The new sorbents developed in this work will be applicable for both mobile and stationary power sources. Also, the sorbents developed in this work can be readily transferred to industrial applications. In addition, a basic understanding of the hydrogen spillover and reverse spillover phenomena will be obtained in this work.