Finding new sources of clean, renewable energy is one of the most pressing issues that humanity must solve. Scientists from all over the globe are working to find a solution. Last month, some great news came out of one of those labs. A crucial step in water-splitting was done with 100 percent efficiency and it brought us that much closer to hydrogen fuel.
What is hydrogen fuel anyway? It is a zero-emission (except for water) fuel that is produced when it is burned with oxygen. Hydrogen fuel uses combustion in internal engines to help power vehicles and even spaceships. In the past, the quest for hydrogen fuel has been discouraged because of the expense to produce hydrogen gas, which the fuel is produced from.
Scientists are well on their way to taking that whole ‘expensive to produce’ part out of the equation. The goal with their studies has been to find a cheap and easy solution for splitting water into its molecular parts. The current process itself doesn’t sound complicated to the layman; you just grab some water and shock it with electricity. Child’s play, right? Maybe, but that process, which produces hydrogen and oxygen, is very expensive.
The first step in splitting water is called reduction. Reduction basically means all of the energy scientists put into the solution came out of the other side. Previous attempts at making this process completely efficient only reached 60 percent, so 100 percent is a true milestone. Not only does this news motivate scientists to continue their research, but it also lends itself to the fact hydrogen fuel could be a reality. Because if the first step could be improved this much, so could others, making the process of producing hydrogen fuel as easy and affordable as possible.
The key to making this process so efficient was using light as the energy source that powered the reaction. Scientists used something called a nanorod to absorb the light. This nanorod was the catalyst for the reaction, not some sort of chemical, which is the usual go to in similar experiments. The nanorods are called photocatalysts and they function by taking in photons produced by the light source and releasing electrons, which is what kicks off the water-splitting. The lead researcher of the experiment, Lilac Amirav, told Phys.org that there is “little to no room” for improvement to this particular process.
As mentioned earlier, there are two parts to the water-splitting process: oxidation and reduction. The entire process requires two molecules of H2O. During oxidation, four hydrogen atoms and an O2 molecule are produced. The O2 molecule is eventually discarded. During reduction, with the addition of electrons, the four hydrogen atoms pair up to form two H2 molecules, which is what produces H2 gas. It is the reduction step that has been made so much more efficient thanks to these experiments. Although there are small tweaks and fixes that can be made to this new process, all signs point to a future with hydrogen fuel!