Organic Hydrogen Storage

Feb 24, 2006

Fossil fuels are limited and polluting, hence the search for alternatives. One suitable and environmentally sound fuel would be hydrogen; unfortunately there are currently few technical possibilities for the construction of safe and efficient hydrogen storage tanks that are suitable for cars. One possible solution to the hydrogen storage problem is to use microporous materials such as zeolites or activated carbons, which have many molecular sizes holes suitable for the containment of hydrogen and can also release it when needed.

Neil McKeown, of Cardiff University, UK, and his collaborators, Peter Budd (University of Manchester) and David Book (University of Birmingham) have chosen a new approach: they have developed a purely organic polymer that can adsorb appreciable quantities of hydrogen.

The molecular chains in most organic polymers are so flexible that they can form tightly packed structures. This means there are no cavities inside, and thus no appreciable internal surface onto which substances could be adsorbed. The chemists thus constructed polymers from interlinked five- and six-membered rings. At defined points in the molecule, two five-membered rings are connected in such a way as to provide a contorted shape to the stiff macromolecular structures. The contorted molecules cannot pack together efficiently and leave gaps and interstices. These “polymers of intrinsic microporosity” (PIMs) have large internal surface areas of over 800 m2 per gram of material — equivalent to the surface area of three tennis courts.

In reproducible synthetic steps, the researchers have produced chemically homogenous materials with a uniform distribution of pore sizes of 0.6–0.7 nm. These ultrasmall pores can absorb and then release between 1.4 and 1.7% hydrogen. Depending on the selection of building blocks the researchers can produce insoluble networks or polymers that are soluble in solvents and can thus be processed into useful shapes like common plastics.

In order for the PIMs to store enough hydrogen to be useful they must be optimized further. “However, there is great potential for tailoring the PIM structure by both chemistry and polymer processing techniques” says McKeown, who anticipates that by the year 2010 they will have succeeded in preparing a PIM capable of storing up to 6% hydrogen.

Author: Neil B. McKeown, Cardiff University (UK),
Title: Towards Polymer-based Hydrogen Storage Materials: Engineering Ultramicroporous Cavities Within Polymers of Intrinsic Microporosity
Angewandte Chemie International Edition 2006, 45, 1804, doi: 10.1002/anie.200504241

Source: Angewandte Chemie

Explore further: Google eyes nanoparticle platform as part of health rethink

add to favorites email to friend print save as pdf

Related Stories

Team advances fuel cell car technology

Jan 29, 2015

Dr. Yossef Elabd, professor in the Artie McFerrin Department of Chemical Engineering at Texas A&M University, has developed two fuel cell vehicle platforms for both present day enhancements and future innovation.

The path to artificial photosynthesis

Jan 21, 2015

Scientists at the Helmholtz Center for Materials and Energy in collaboration with the School of Chemistry and ARC Centre of Excellence for Electromaterials Science at Monash University, Australia, have precisely ...

Future batteries: Lithium-sulfur with a graphene wrapper

Dec 16, 2014

What do you get when you wrap a thin sheet of the "wonder material" graphene around a novel multifunctional sulfur electrode that combines an energy storage unit and electron/ion transfer networks? An extremely ...

Recommended for you

DNA nanoswitches reveal how life's molecules connect

Jan 30, 2015

A complex interplay of molecular components governs almost all aspects of biological sciences - healthy organism development, disease progression, and drug efficacy are all dependent on the way life's molecules ...

Holes in valence bands of nanodiamonds discovered

Jan 28, 2015

Nanodiamonds are tiny crystals only a few nanometers in size. While they possess the crystalline structure of diamonds, their properties diverge considerably from those of their big brothers, because their ...

Demystifying nanocrystal solar cells

Jan 28, 2015

ETH researchers have developed a comprehensive model to explain how electrons flow inside new types of solar cells made of tiny crystals. The model allows for a better understanding of such cells and may ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.