1. Bioelectrochemical Power-to-Gas: State of the Art and Future Perspectives 
Florian Geppert, Dandan Liu, Mieke van Eerten-Jansen, Eckhard Weidner, Cees Buisman, Annemiek ter Heijne 
Trends in Biotechnology 
Volume 34, Issue 11, Pages (November 2016)
DOI: /j.tibtech
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2. Figure 1
Schematic representation of a two-chamber methane-producing bioelectrochemical system (adapted from [23]). Typically, the anodic oxidation of water is coupled to the production of methane at the cathode.
Trends in Biotechnology  , DOI: ( /j.tibtech )
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3. Figure I
(A) Overview of oxidation and reduction reactions for methane-producing bioelectrochemical systems (BESs). The standard electrode potential for each reaction was calculated from the Gibb's free energy [38] at standard conditions (1M or 1bar for all chemicals involved in the reaction, pH 7 and 298K). (B) Mechanisms of methane-producing BESs: 1, direct electron transfer for methane production by electrochemical reduction or catalyzed by methanogens (green ellipses); 2, mediated electron transfer for methane production via hydrogen generated by hydrogen-producing microorganism (orange ellipse); 3. mediated electron transfer for methane production via acetate (or formic acid) generated by acetate- (or formic acid-) producing microorganisms (violet ellipse).
Trends in Biotechnology  , DOI: ( /j.tibtech )
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