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 versus 35 F g(-1) for the AC supercapacitor, i.e. a 29% increase after POM integration into the AC matrix. (C) 2012 Elsevier B.V. All rights reserved.