%0 Journal Article
%T Material Demands for Storage Technologies in a Hydrogen Economy
%A M. Kunowsky
%A J. P. Marco-L¨®zar
%A A. Linares-Solano
%J Journal of Renewable Energy
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/878329
%X A hydrogen economy is needed, in order to resolve current environmental and energy-related problems. For the introduction of hydrogen as an important energy vector, sophisticated materials are required. This paper provides a brief overview of the subject, with a focus on hydrogen storage technologies for mobile applications. The unique properties of hydrogen are addressed, from which its advantages and challenges can be derived. Different hydrogen storage technologies are described and evaluated, including compression, liquefaction, and metal hydrides, as well as porous materials. This latter class of materials is outlined in more detail, explaining the physisorption interaction which leads to the adsorption of hydrogen molecules and discussing the material characteristics which are required for hydrogen storage application. Finally, a short survey of different porous materials is given which are currently investigated for hydrogen storage, including zeolites, metal organic frameworks (MOFs), covalent organic frameworks (COFs), porous polymers, aerogels, boron nitride materials, and activated carbon materials. 1. Motivation Today¡¯s energy sector is accompanied by a number of environmental inconveniences. In order to overcome those problems, future energy concepts have to be put into practice. In particular, renewable energies are needed, because (i) fossil energy promotes global warming and environmental contamination, (ii) the supply of nonrenewable energy sources is finite, and (iii) nuclear energy presents a serious danger due to its radioactive waste products. Among renewable energies, technologies for hydrogen storage will be an important piece of the jigsaw. The world¡¯s current energy supplies are mainly based on fossil energy resources. These resources have their origin in organic (and therefore carbon-containing) compounds, which have been converted throughout millions of years. By burning them today, these resources are reintroduced into the natural carbon cycle and increase the CO2 content of the atmosphere. CO2 gas increases the world¡¯s greenhouse effect, leading to global warming [1]. In Figure 1 it can be seen that, since the industrialization in the 19th century, the atmospheric CO2 content is continuously rising. Also the evolution of the global temperature is shown in Figure 1. For the same time period, an overall increasing tendency can be observed, which suggests a relationship between both trends that could be something more than casual. Figure 1: Global temperature (red) and CO 2 emissions (blue) over the past decades [ 14¨C 16].
%U http://www.hindawi.com/journals/jre/2013/878329/