Water as fuel of the future

It is known that the main obstacle to the fully introduction of renewable energy sources (primarily the energy of the Sun) are the problems of accumulating this very energy and its transportation. The batteries are not cheap and bulky, and with transformations of light energy into electricity, and then significant losses are inevitable into mechanical energy.

And how do you not recall the processes of photosynthesis inherent in the leaves of ordinary plants, which allow you to store solar energy in the form of chemical compounds? The developed systems of artificial photosynthesis are based on the processes of photoelectric electrolysis of water and are largely similar to the redox batteries and fuel elements, but you can go further and get more traditional types of fuel.

Researchers from the California Technological Institute and the National Laboratory of Lawrence in Berkeley Lab (Berkeley Lab) in two years managed to practically double the number of well -known formations that are potentially suitable for obtaining “solar fuel”, which can replace coal, oil and other fossil types of combustible [1].

“Solar fuel”, the elements of which are taken from the natural environment (sunlight, water and carbon dioxide - CO2), and after use, reversibly returned there, is the long -standing dream of all champions of pure energy. Scientists have long been busy with studies of the vast class of chemical compounds, potentially suitable for use in such a quality - from gaseous hydrogen to liquid hydrocarbons - however, the production of any “combustible” does not eliminate the need to split water molecules.

We all know that each water molecule contains an oxygen atom and two hydrogen atoms. If you remove these hydrogen atoms from the water, and then connect them in pairs into hydrogen molecules, you can get highly effective combustible gas, which in combination with CO2 can also give liquid hydrocarbons - familiar and convenient for transportation and storage. The problem, however, is that in ordinary conditions, it is not so easy to split the water molecule under the influence of sunlight alone (otherwise the ocean would not cover most of the surface of our planet). Special catalysts can help.

In order to obtain “solar fuel” suitable for practical use, it is necessary to select inexpensive and effective compounds, in the presence of which there would be a breakdown of water molecules using visible or ultraviolet light as an energy source.

A new approach to the programmable synthesis of chemical compounds - the so -called photoelectro -skatalizers (photographs) - allows us to hope for the appearance of commercially viable technology of artificial photosynthesis in the near future.

Over the past four decades, 16 such compounds have been identified. And now, using the new method of quick identification of the materials received, a group of researchers led by John Gregoire from Kalthekh and Jeffrey Niton and Yan Tsimin (Jeffrey Neaton and Qimin Yan) from the Berkeleevsky laboratory found another 12 new promising photoelectric [2] appeared on March 6, 2017 in the Online issue of Procedings of the National Academy of Sciences - PNAS) . The new method was developed as part of a partnership with the Joint Center for Artificial Photosynthesis (Joint Center for Artificial Photosynthesis - JCAP).

“It is extremely important that in this work, which combines an experimental and theoretical approach and is based on interdisciplinary research, we not only replenished the already well-known list due to the identification of several new compounds (potentially suitable for the production of“ solar fuel ”), but were also able to find out something new about the basic electronic structure of the materials themselves,” Jeffrey Neton emphasized, heading, heading. Molecular Foundry division.

If previously long -term testing procedures for each individual compound (for use in specific applications) were required, now J. Greguar and his colleagues were able to significantly speed up this process. Due to the combination of calculated and experimental data in a single database of potentially interesting connections, they conduct high -performance computer screening studies of the alleged properties of materials, and then test the most promising candidates using experimental installations with high throughput.

In the work described in PNAS , 174 vanadats were studied - compounds containing vanadium oxides along with other elements of the periodic table (primarily with metals - iron, copper, nickel, bismuth), which made it possible to identify a new “prolific” class of photographic materials for the production of chemical fuel from sunlight.

“Our group managed to bring together the possibilities of theory, modeling the properties of new components on supercomputers and new experiments performed with high throughput. Thus, we have learned to generate scientific knowledge with an unprecedented speed, ”concludes John Greguar.

Maxim Borisov

1. CALTECH.EDU/News/new-Materials-coup-turn-water-fuel-future-54294

2. Http://resolver.caltech.edu/caltechauthors:2030306-150101767