Climate change and dwindling supplies of fossil fuels are driving research and investment in alternative forms of energy. One such alternative is hydrogen – a clean, green fuel with a plentiful supply on earth.
Now, scientists funded by the Research Councils UK Energy Programme are working to identify hydrogen storage materials for the fuel tanks of the future.
A key component for future greener transport and energy supply lies in a safer, cheaper and more efficient method of hydrogen storage. Existing approaches are expensive and cumbersome, either converting hydrogen into a liquid at -253°C, or storing hydrogen gas at very high pressure. Solid state hydrogen storage materials offer the greatest promise for widespread uptake of hydrogen as a fuel. The Grand Challenge for hydrogen storage materials is that they must have an energy density similar to petrol, operate close to room temperature and atmospheric pressure, release and absorb hydrogen quickly and be cheap to manufacture.
A team of scientists, lead by Professor Bill David, from the ISIS neutron source at the Science and Technology Facilities Council's Rutherford Appleton Laboratory and from the University of Oxford are developing new materials that could put hydrogen power onto our roads and into our homes. They are synthesising hundreds of new materials and analysing the most promising using neutron diffraction at ISIS.
Professor David, senior research fellow at ISIS, says that neutrons are essential in the search for new hydrogen storage materials.
“Neutrons are without doubt the best way to see hydrogen entering and leaving these storage materials and this enables us to identify the most promising storage options,” he says.
So far, ISIS has enabled the design and discovery of ultra-lightweight hydrogen-rich materials that hold upwards of ten per cent of their own weight in hydrogen. Amazingly they contain a higher density of hydrogen than liquid hydrogen itself.
“We investigate our best hydrogen storage materials by mimicking their performance in a car,” says Professor David. “We cycle the hydrogen in and out of these stores and monitor the hydrogen weight loss and gain. The unique extra dimension to our experiments is that we do all of these measurements in the neutron beam in real time allowing us to see what is happening at an atomic level.
“Essentially, neutrons at ISIS allow us to look into the hydrogen fuel tanks of the future.”