Co9S8/CoS@S, N co-doped porous carbon derived from MOFs as an efficient catalyst for the oxygen evolution reaction

Abstract

Co9S8/CoS@S,N co-doped porous carbon were successfully prepared by using thiourea and Co-based metal organic frameworks (Co-MOFs) as precursor and template. The porous carbon with a large surface area provides a favorable transport environment for the electrons and ions in the electrolyte. Co9S8/CoS nanoparticles and S doping may reduce the Ohmic series resistance (Rs) and charge transfer resistance (Rct) of the electrocatalysts. The prepared Co-1.8/NC-0.3 composite shows excellent electrocatalytic performance for oxygen evolution reaction (OER) with a low overpotential of 180 mV at 10 mA cm−2 and high durability in 1 M KOH solution. The Rct and Rs values of Co-1.8/NC-0.3 are 5.01 × 10−6 and 1.72Ω. The lowest Rct indicates that the catalysts has lower resistance and more OER activities at the electrode/electrolyte interface in comparison with the other catalyst.