Catalysts

The description of the operation of a fuel cell above is a simplification because it omits one key feature of the reaction between hydrogen and oxygen. Although hydrogen atoms and oxygen atoms will react spontaneously to form water, both hydrogen and oxygen are found (at room temperature) in the molecular forms H2 and O2. These will not react spontaneously and the hydrogen and oxygen molecules must be split before the reaction will proceed.

One method of splitting the molecules is to raise their temperature. Thus a flame will split sufficient of the molecules to start the reaction which then generates enough heat spontaneously to keep the reaction going. Some fuel cell designs use high temperatures too.

The alternative is to use a catalyst. A metal such as platinum will promote the splitting of both hydrogen and oxygen molecules at low temperatures and the resulting atoms will then react in a fuel cell. However platinum is very expensive. This has a significant effect on the cost of low-temperature fuel cells.

Renewable Energy 101

Renewable Energy 101

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable. The usage of renewable energy sources is very important when considering the sustainability of the existing energy usage of the world. While there is currently an abundance of non-renewable energy sources, such as nuclear fuels, these energy sources are depleting. In addition to being a non-renewable supply, the non-renewable energy sources release emissions into the air, which has an adverse effect on the environment.

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