Perovskite La1−xKxCoO3−δ (0 ≤ x ≤ 0.5): a novel bifunctional OER/ORR electrocatalyst and supercapacitive charge storage electrode in a neutral Na2SO4 electrolyte

La 1− x K x CoO 3− δ (0 ≤ x ≤ 0.5) display a remarkable pseudocapacitive charge storage capacitance in a neutral 0.5 M Na 2 SO 4 electrolyte and superior electrocatalytic activities for the OER and ORR in a 1 M KOH electrolyte.