Energy by Microbial Fuel Cells: Scientometric global synthesis and challenges

The scarcity of natural resources and the growing need for electricity requires the development of new technologies that can provide alternatives to traditional energy sources in a sustainable fashion. One of the promising opportunities currently under development is Microbial Fuel Cell (MFC) technology. The aim of our study was to analyze the relevant literature related to MFCs through a scientometric approach in order to produce a comprehensive synthesis, something that is lacking. We identified 19671 relevant studies in the field and examined 3427 papers in detail in a systematic review performed in the ISI database Web of Science. Our primary goals were to: (i) determine the temporal evolution of publications, (ii) reveal which journals publish on the subject, (iii) show the global distribution of MFC research and funding perspectives, (iv) uncover the scales of application of the technology, (v) account for the most commonly used substrates, (vi) find out whether pure or mixed cultures of microorganisms are involved and (vii) determine the major species used. We detected a substantial increase in publications after 2006. We found that the US and East Asia are the most promising locations for the development of MFCs, given both the number of publications and the amount of financial investment in research and development. The main technological barrier to the wide-spread use of MFCs is the scale of application, restricted to small prototypes insufficient to generate electricity for practical purposes. The most cited substrate was wastewater, both domestic and industrial, demonstrating the great potential of MFCs in wastewater treatment. Finally, our results demonstrated that there is a wide variety of microorganisms capable of generating electricity, although the great majority of papers focus on a few well-established species. Taken together, our results can help research and application in this field on a global level perspective.