MnCO3 microcubes as an inexpensive catalyst for oxygen evolution reaction

In this study, MnCO3 microcubes (MCs) were successfully synthesized via a simple hydrothermal synthesis method using a fixed amount of MnCl2, urea, and various concentrations (0.2, 0.4, and 0.8 g) of cetyltrimethylammonium bromide (CTAB); these microcubes were labeled as MC-1, MC-2, and MC-3, respectively. The synthesized MCs were used as efficient nonprecious electrocatalysts for the OER in an alkaline medium. Compared with MC-2 and MC-3, MC-1 exhibited a high OER activity, which was evidenced by a lower overpotential of 350 mV at a current density of 50 mA g−1, a small Tafel slope of 109 mV dec-1, and high durability.