Cover Picture: Fast and Reversible Surface Redox Reaction in Nanocrystalline Vanadium Nitride Supercapacitors (Adv. Mater. 9/2006)

Abstract The cover shows a high magnification transmission electron microscopy image of VN nanoparticles that exhibit enhanced supercapacitor response. The high capacitance is due to V undergoing a series of highly reversible redox reactions. These involve a transition between II–IV oxidation states via hydroxyl bonding confined to a few atomic layers of vanadium oxides formed on the surface of the underlying nitride, as discussed by Kumta and co‐workers on p. 1178.