Electrochemical performances of nickel deposited zeolitic-imidazolate framework-67 for oxygen reduction and evolution reactions in alkaline medium.

• Nickel deposited catalysts using Zeolitic-Imidazolate Frameworks-67 as a precursor were synthesized. • The catalysts exhibited higher catalytic activities for oxygen reduction and evolution reactions. • The catalysts show low overpotential and high stability. Zeolitic imidazolate framework containing cobalt and nickel (Co- and Ni-ZIF-67) were used as a precursor to perform Ni deposition, in order to obtain enhanced catalytic activity and nanocatalysts. Co or Ni embedded in the carbon nanotubes (CNTs) were obtained by the heat treatment of Co- or Ni-ZIF-67. On Co or Ni embedded CNTs, Ni-deposition was performed to obtain the Ni-deposited catalysts, Ni-CNT-(Co or Ni), which have a higher surface area of 136.7 and 259 m2/g, respectively. These catalysts exhibit superior performance, low overpotential, and high stability for both oxygen reduction and evolution reactions. The superior performance is attributed to metal deposition, which creates highly active catalytic sites and has potential application as a catalyst for the rechargeable zinc-air battery. [ABSTRACT FROM AUTHOR]