Bioelectrochemical systems for energy and materials conversion [article]

Tanja Vidakovič-Koch, Universitäts- Und Landesbibliothek Sachsen-Anhalt, Martin-Luther Universität, Kai Sundmacher
2019
In bioelectrochemical devices, enzymes, as catalytic parts, are smartly combined with electroconductive surfaces. In this way electroconductive materials might replace one of the natural enzyme substrates in a so-called direct electron transfer mechanism (DET). Alternatively, an artificial enzyme substrate, a so-called mediator, might be used and regenerated electrochemically via a mediated electron transfer mechanism (MET). Currently, there is a high level of interest in the use of enzymes in
more » ... use of enzymes in technical systems, which is mainly triggered by their high selectivity and excellent catalytic activity under mild conditions (neutral pH, low temperature). These features favor applications where technical systems respond selectively to components of complex mixtures as expected in biosensors. Similarly, in enzymatic fuel cells high selectivity enables a simplified fuel cell design where classical fuel cell components, such as separator, fuel cell tank and even housing, can be avoided. This design is beneficial for so-called "energy harvesting" where the fuel/oxidant is directly extracted out of the environment and enables miniaturization beyond the level possible for other electrochemical devices (e.g. conventional batteries or fuel cells). For these reasons enzymatic fuel cells are considered to be promising implantable miniaturized power sources for medical electronic devices such as pacemakers, medical pumps, sensors etc. In addition to sensing and energy conversion applications, electroenzymatic systems offer good prospects for chemical production. Chemicals can be produced in both enzymatic fuel cells and electroenzymatic reactors. In the former case, partial oxidation products of typical "fuels" such as glucose, methanol and ethanol, can be obtained. In the latter case selective reduction processes are targeted where, for example, CO2 can be converted into methanol (or formic acid or formaldehyde). The level of the oxidation/reduction process depends on the length of the enzymatic cascade. The high enzyme selectivit [...]
doi:10.25673/14087 fatcat:icmewvptsjeyzhko7lxc4miqau