In situ growth of (NH4)2V10O25·8H2O urchin-like hierarchical arrays as superior electrodes for all-solid-state supercapacitors

(NH₄)₂V₁₀O₂₅·8H₂O urchin-like hierarchical structures were grown in situ on highly conductive nickel foam substrates as advanced electrodes for asymmetric supercapacitors, the performance of which exceeds that of most recently reported vanadates and polyvanadates.