Fuel Cell (IMAGE)
Caption
This is an assembled H2/N2 fuel cell. Carbon paper electrodes are inserted into the anodic (left hand side) and cathodic (right hand side) chambers of the fuel cell. Both chambers are separated by a proton exchange membrane. The anodic chamber contains the fuel (100 percent hydrogen), an electron carrier (methylviologen) and a purified metalloenzyme that can oxidize hydrogen (hydrogenase). The cathodic chamber contains the oxidant (100% nitrogen), an electron carrier (methylviologen) and a purified metalloenzyme (nitrogenase) that can reduce nitrogen gas to ammonia. The fuel cell is connected to a potentiostat, where a low potential difference is applied to the fuel cell. At the anode, hydrogenase oxidizes hydrogen gas, forming protons and electrons, and the electrons are shuttled to the anodic carbon paper electrode while the protons are transported across the proton exchange membrane to the cathodic chamber. Later, those electrons are supplied (via the cathodic carbon paper electrode and an electron carrier) to nitrogenase, where the enzyme combines electrons and protons to reduce nitrogen gas to ammonia.
Credit
Ross Milton.
Usage Restrictions
Credit Ross Milton
License
Licensed content