Hybrid electrodes based on polyoxometalate–carbon materials for electrochemical supercapacitors

Hybrid electroactive materials based on polyoxometalate‐adsorbed activated carbons have been developed for the first time as electrodes for supercapacitors. By combining the double layer capacitance of a high‐surface area material with the reversible redox activity of a polyoxometalate (POM), enhanced electrochemical performance is obtained. In this paper, phosphomolybdic acid H3PMo12O40 (PMo12) was anchored to an activated carbon providing 160 F g− 1 and 183 F g− 1 for the positive and negative hybrid electrodes, respectively (at 2 A g− 1), substantially larger than the 136 F g− 1 of the unmodified activated carbon. This translates to a cell capacitance for the AC–POM supercapacitor is 45 F g− 1 versus 35 F g− 1 for the AC supercapacitor, i.e. a 29% increase after POM integration into the AC matrix.