Electrochemical Step Towards Better Hydrogen Storage

Good metal-based systems for hydrogen storage cannot be developed without knowing how this element permeates through metals. Researchers at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw managed to apply a user-friendly electrochemical method to study hydrogen diffusion in highly reactive metals.

Hydrogen is seen as a versatile energy carrier for the future. Unfortunately, the element practically does not occur in the free state on Earth. Therefore, it must be first generated (e.g., by electrolysis of water), then stored, to be finally used — ideally in fuel cells transforming chemical energy directly into electrical one. Hydrogen storage represents, however, a serious challenge. The drawbacks of conventional storage tanks for gaseous and liquid hydrogen force us to look for other solutions. One of the promising methods for hydrogen storage makes use of the capability of some metals and alloys to easily uptake this element. The development of efficient hydrogen storage systems requires, however, a detailed knowledge on how hydrogen diffuses in metals.

Hydrogen permeation through metals can be conveniently studied with electrochemical methods. These methods fail, however, for metals where the diffusion of hydrogen is relatively slow, and also in cases where metals strongly react with aqueous electrolyte solutions. The problem relates in particular to magnesium and magnesium alloys that are considered the most attractive materials for hydrogen storage. “We managed to overcome this obstacle”, says Prof. Tadeusz Zakroczymski, whose team at the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw has been for many years carrying out comprehensive research on hydrogen permeation, diffusion and uptake in metals.

Written by Antoni Szafranski. To read the full article, click here.

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Solar Power Heads in a New Direction: Thinner

Cambridge, Mass. — Most efforts at improving solar cells have focused on increasing the efficiency of their energy conversion, or on lowering the cost of manufacturing. But now MIT researchers are opening another avenue for improvement, aiming to produce the thinnest and most lightweight solar panels possible.

Such panels, which have the potential to surpass any substance other than reactor-grade uranium in terms of energy produced per pound of material, could be made from stacked sheets of one-molecule-thick materials such as graphene or molybdenum disulfide.

Jeffrey Grossman, the Carl Richard Soderberg Associate Professor of Power Engineering at MIT, says the new approach “pushes towards the ultimate power conversion possible from a material” for solar power. Grossman is the senior author of anew paper describing this approach, published in the journal Nano Letters.

Although scientists have devoted considerable attention in recent years to the potential of two-dimensional materials such as graphene, Grossman says, there has been little study of their potential for solar applications. It turns out, he says, “they’re not only OK, but it’s amazing how well they do.”

Written by David Chandler. To read the full article, click here