Abstract
In this review, recent developments in enzymatic biofuel cell (EBFC) technology are reviewed. A general introduction to EBFCs, including their operating principles and applications, is provided. The electron transfer mechanism, mediator and enzyme materials (anode and cathode) are discussed. EBFCs are promising for sustainable green energy applications; however, they are still at an early stage of development, with many yet-to-be-resolved fundamental scientific and engineering problems. Two critical problems are short lifetime and poor power density, both of which are related to enzyme stability, electron transfer rate, and enzyme loading. To achieve the practical application of EBFCs, a promising approach is to use porous carbon materials as enzyme supports. Strategies for the design of hierarchically structured supports with both mesopores and macropores are considered. The large surface area of these mesoporous materials can increase the enzyme loading and electron transfer efficiency. The macropores enable efficient biocatalyst and fuel transport. The essential properties of the resulting materials with respect to the EBFC application are also discussed. A combination of electron transfer technology and porous carbon material would be helpful in achieving a much higher and stable current output, thus contributing to a practical advance in the sustainable energy field.
