which promise to offer high power density and
high specific energy. By combining an anionic redox pair of Zn(OH)4
2−/Zn (−1.22 V versus
SHE) in base with a cationic redox pair of Ce4+/Ce3+ (1.74 V versus SHE) in acid, Zn-Ce DMFBs
offer standard cell voltage as high as 2.96 V. The working principles of Zn-Ce DMFB are shown
in Figure 13.