Hydrogen

Hydrogen

Colorless, highly flammable gas. It is the lightest element. It was discovered by the Englishman Henry Cavendish in 1766. The name is derived from the Greek words hydro (water) and genēs (generator). It is assumed that it was the first element when the universe was created during the Big Bang. In contrast, its abundance in pure form on the Earth today is negligible since most of it is bound to other elements, for example, in water.

A promising means of solving the general problem of energy supply is the “tamed” hydrogen bomb, in which helium and energy are produced through the fusion of hydrogen nuclei in a controlled manner, using so-called fusion reactors [1].

Apart from this nuclear process, there are less efficient, but quite attractive chemical procedures for extracting energy from this element: companies like BMW have built prototypes of cars that burn hydrogen by reacting chemically with oxygen, something that is already performed in space ships [2].

For the production of the necessary hydrogen, a promising method for the near future is photocatalysis, which is the decomposition of water into hydrogen and oxygen in the presence of light and a catalyst, for example, a ruthenium compound (see Element No. 44) [3, 4]. Note that living organisms, for example, purple bacteria in salt water, the so-called halobacteria, also obtain hydrogen using light [5].

[1] N. Keishivo, Nuclear Fusion, Cambridge University Press, Cambridge, UK, 1980. ISBN: 978-0521113540
[2] J. Ogden, Fuel Cells and More, Scientific American 2006, 295(3), 94–101. DOI: 10.1038/scientificamerican0906-94
[3] A. Kudo et al.,Strategies for the Development of Visible-light-driven Photocatalysts for Water Splitting, Chem. Lett. 2004, 33, 1534–1539. DOI: 10.1246/cl.2004.1534
[4] Accounts of Chemical Research: Full volume dedicated to “Artificial Photosynthesis”, 2009, 42(12). Link
[5] W. Stoeckenieus, The Purple Membrane of Salt-loving Bacteria, Scientific American 1976, 234(6), 38–46. DOI: 10.1038/scientificamerican0676-38

Through many faces
I have returned
to my father.
He stands in front of me
as if he were a scripture
and lets me look
through his telescope.
He is back with me,
as present
as before.

Through many faces
we have returned
to the source.
Everything was Hydrogen
but the Earth
has bound it.
Now
it’s being freed.
It invites us
to move machines,
arms and legs
a billion times,
letting us explore
comets, moons
and planets.

It is back
with us,
as present
as before.