A team of researchers from Stanford University has published the results of testing an experimental hydrogen generation plant. The raw material in it is ordinary water, and this technology is distinguished by the principle of operation, which is copied from human lungs. It is simpler, more efficient and cheaper than traditional methods of generating this gas.
Scientists copied a membrane device for separating gases from the lung, only in this case, not only oxygen, but also hydrogen is extracted from the initial mixture, which together form a fuel mixture. To increase the efficiency of water splitting, electrocatalysts made of platinum and gold are used; the process itself is initiated when an electric current is applied to the liquid. The highlight is in the membrane design.
Geometry plays a key role, the study authors say. They applied a layer of metal catalysts to one side of a 12-nanometer-thick polymer film and created a series of pores on the other. They are too small for the passage of water molecules, but gas molecules pass freely, and, thanks to catalysts, the whole process is accelerated many times, requiring 32% less energy consumption than when using typical carbon membranes.
The film was folded into a kind of bag and placed in water, now all the generated hydrogen fuel will accumulate inside. Due to the special shape of the membrane surface, bubbles do not form on it during the process, the reactions proceed evenly, the pressure changes gradually and there is practically no wear of the catalytic layer - 3% loss after 250 cycles versus 74% after 70 cycles for carbon membranes. Now scientists have to figure out how to make this cellular system, by analogy with the same human lungs.