Apparently the working of the hydrogen-cell, which constitute the "core" of the hydrogen-technologies, is easy. The cell works on the principle of the inversion of the electrolysis of the water.
The recombination of hydrogen and oxygen takes place in the cell in a particular membrane, which transports iones towards opposite directions. The presence of colloidal platinum primes the reaction of dissociation of gaseous hydrogen and oxygen into ions.
The majority of the car industries produces cars like our model - hydrogen-feeded. But not many people can afford a car like this because of its price.
So-called fuel cell (and should be called "hydrogen cell") consists of an anode made of a metal with high corrosion resistance, like aluminum, copper or inox, covered by the colloidal platinum which works as a catalyst. Electrodes have usually wavy shape or they form a grid, for example 0.5x0.5 mm. Between electrodes a thin (0.12-0.25 mm) polymeric membrane is placed, working as a sieve for protons. Platinum assures dissociation of the molecular hydrogen into a proton and electron, according to the scheme:
Protons migrate through the membrane (which is transparent only to them) to the cathode and electrons are captured by the anode and then move to the external electric circuit. On the cathode they are captured by protons and the water molecule is formed with oxygen.
In sum, oxygen is supplied to the cathode region and hydrogen to the anode one and water is produced as a result of the reaction. (A layer of colloidal platinum is placed also on the cathode).
On the cathode we also have a layer of platinum (catalyst). Water is a by-product of the cell's operation.
Other types of membranes (for example ceramic ones, working at high temperatures) and other types of reactions can be also used in fuel cells. The picture shows Proton Exchange Membrane Fuel Cell. The efficiency of such a cell is about 0.5 to 2 W for 1 cm2, the voltage is 0,5 to 1 V and the current up to 2 A from 1 cm2 of the cell.
The cell is packed in a hermetic plastic box and the current is collected form the external electrodes.
The efficiency of such a cell is about 0.5 to 2 W for 1 cm2, the voltage is 0,5 to 1 V and the current up to 2 A from 1 cm2 of the cell.
A massive use of fuel cells in transportation and energy production would reduce the emission of CO2 by 40% - 60%, and the emission of nitrogen oxides by 50% -90%.