Nanoflower-like high-entropy Ni–Fe–Cr–Mn–Co (oxy)hydroxides for oxygen evolution

In 1 M KOH and in 0.5 M NaCl + 1 M KOH, the overpotential of nanoflower-like FeNiCrMnCoOOH/NF is 201 and 223 mV, respectively, at a current density of 10 mA cm −2 .