Cobalt-doping in hierarchical Ni3S2 nanorod arrays enables high areal capacitance

Cobalt-doped Ni₃S₂ nanorod arrays have been prepared via a hydrothermal method. As a free-standing electrode, the Co-Ni₃S₂ demonstrates ultrahigh areal capacitance, affording the Co-Ni₃S₂//FeOOH hybrid supercapacitor a high energy density.