What is the biofuel?
Biofuel cell is a device that uses biological materials to produce electricity in a direct way through redox reactions. This contrasts with the conventional use of biofuels for the production of electricity from the heat provided by the combustion of the material. The principle of biofuel technology is to imitate various natural processes that are used to produce energy in living organisms. In some cases, bacteria can play a role in these fuel cells. Since 2011, biofuel cells have showed potential as an alternative energy source and in various medical and bioointed applications.
living organisms gain energy from carbohydrate oxidation, which are created by photosynthesis in plants and used as food in animals. Enzymes facilitate reactions in which carbohydrates are converted into carbon dioxide and water by removing electrons, which are then stored in adenosine triphosphate (ATP) molecules. In biofuel cell, electrons produced by oxidation of organic molecules - usually coalHydrates, as in living organisms - are used to generate electric current. The idea of using these biological processes to produce electricity has existed since the 1960s, but timely attempts to create practical work biofuels have encountered difficulty.
Biofuel Cell will usually consist of a container divided into two sections through a permeable barrier. In one part it provides oxidation of carbohydrates - for example glucose - electrons. In the second part there is a reduction reaction that uses these electrons. By connecting these two electrodes, the electrode can produce a current in the oxidation part - the anode - with an electrode in the reduction part - the cathode.
One of the biggest practical problems that prevents biofuel cell development from finding an efficiency on how to get electrons released from carbohydrates to the anode. Electrons are initially stored in the oxidation enzyme and in a natural process by Byly chemically transferred to molecules, etc. There are two possible methods of electron extract from enzyme to anode in biofuel cell.
In the direct electron transmission method (DET), the enzyme must be connected to the anode. This can be done by chemically or other methods, such as the construction of an anode from the mesh of carbon nanotubes, on which the enzyme is adsorbed. These methods result in reduced activity in the enzyme and subsequent loss of efficiency, but at the time of writing, the area of ongoing research and improved techniques can be developed.
Another electron transmission method is known as mediated electron transmission (MET). This does not require the enzyme to be in contact with the anode; Instead, electrons are transferred to another molecule with a lower redox potential, which then gives up electrons to the anode. This compound, known as a mediator, must also have higher redox potential than the anode. This next step involves loss of energy, and therefore the fuel cell is less effective in practice than it could be theoretically.
BIOfuel cells are an area of active research and are examined by various possible solutions to these problems. The possibilities include the use of bacteria in microbial fuel cells. Iron -reducing bacteria that live in anaerobic conditions show a special promise because they naturally reduce iron in its oxidation state +3 to its oxidation state +2. Iron can then give up the electron in the anode, return to +3 and act as a natural mediator molecule by transferring electrons from bacteria to anode.
The main advantages of biofuels are that they are not contaminated, do not require expensive catalysts and use conventional, cheap and easily renewable raw materials. The main disadvantages of biofuel cells is their inefficiency and low power. Since 2011, however, there are hope that these problems can be overcome and open a new range of options. These include not only cheap, clean and renewable energy, but also prospects for implanted biofuel cells that run on the fabrics produced by the body that are used to powerVotnice means such as pacemakers.