Oxophilicity of the surface plays a very important role in electrolysis

Monday, October 26th, 2020

Chemist Ian McCrum used a special platinum crystal to bring sustainable hydrogen one step closer:

To understand what is so special about this crystal, we need to zoom in on the surface of the platinum. This is not flat and smooth, but irregular with tiny steps and kinks. And it is precisely at these irregularities that chemical reactions take place. McCrum designed the special crystal in such a way that the surface has the same number of these irregularities throughout the crystal. He then decorated the edges with different metals, such as ruthenium and molybdenum. In this way, he ensured that all the electrodes had exactly the same atomic structure, but each time with a different metal in the edges. This enabled him to vary the interaction of the electrode with the oxygen atom of water in a systematic and well-defined way.

Measurements then began, with a surprising outcome. Marc Koper says, “Our breakthrough is that there appears to be a clear link between the activity of the electrode for making hydrogen and the degree to which the metal in the edge binds to the oxygen atom of water.” The latter is also known as oxophilicity, with oxophilic literally meaning oxygen-loving. “We have even found an optimum for this oxophilicity,” says Koper. “We have now definitively established that the oxophilicity of the surface plays a very important role in electrolysis.”

Comments

  1. Bob Sykes says:

    Like wind and solar, hydrogen is a niche technology. Catalysts make chemical processes go faster by reducing the activation energy, but they do not change the overall reaction energy. Moreover, because of the second law, the energy needed to produce hydrogen from water exceed the energy obtained by reoxidizing it.

    There are other problems. Hydrogen does not condense at practical temperatures and pressures, and so it is difficult to store. There is also the issue of hydrogen embrittlement of steel, which affects not only storage tanks but also pipelines. As a practical matter this means that hydrogen must be made where and when it is going to be used.

    The percentage of academic scientists engaged in misrepresenting (sometimes lying about) research is surprising large (a third?). In part this is because there is no ethical code for scientists, and they are free from supervision and monitoring.

  2. Gavin Longmuir says:

    Well stated, Mr. Sykes!

    Conceptually, hydrogen is no different from an electric cable — not a source of power, merely a way of transporting power from where it is generated to where it is used. Even if all the many other problems with hydrogen could be magically solved, there would still be the Big Issue of how to generate the energy to split water into oxygen & hydrogen in the first place.

    We are seeing what President Eisenhower warned about in his Farewell Speech — the domination of “science” by the Federal research dollar. The easy (albeit dishonest) way forward for the “scientist” who wants to get research funds, publications, and academic tenure is to abase herself before whatever today’s Political Correctness demands.

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