Fig. 5
a Schematics of the primary configuration of a Zn–air battery. b Polarization curves of zinc–air battery based on MnO-600 or commercial Pt/C catalyst as cathode: cathode area: 3 cm2; loading amount: 2 mg cm−2; temperature: ~ 20 °C; c longtime durability of zinc–air battery by using MnO-600 or commercial Pt/C as cathode catalyst at the current densities of 2, 5, 10 and 20 mA cm−2. d Galvanostatic discharge–charge cycling curve at 10 mA cm−2 of the zinc–air battery using MnO-600 or Pt/C catalyst. e Photographs of different light-emitting diode (1.5 V, 2–2.2 V)