Three-dimensionally ordered mesoporous trimetal sulfide as efficient electrocatalyst for rechargeable zinc-air batteries

Electrocatalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are indispensable in rechargeable zinc-air batteries. Herein, three-dimensional ordered macroporous N-doped trimetal sulfides (3DOM N-CO0.8Fe0.1Ni0.1Sx) bifunctional catalyst has been developed. The 3DOM porous structure provides rich channels for mass transportation and exposure of catalytic active sites. Together with the synergistic effect of trimetallic sulfide and N-doped carbon layer, this 3DOM catalyst exhibits excellent bifunctional catalytic activity, delivering an ORR half-wave potential of 0.80 V (vs RHE) and low OER overpotential of 370 mV at current density of 10 mA cm(-2). The zinc-air battery with 3DOM N-Co0.8Fe0.1Ni0.1Sx achieves a stable cyclability with a lifetime of over 200 h at 10 mA cm(-2). In-situ Raman analysis reveals that, during the OER process, surface reconstitution of the sulfide catalyst occurs, forming oxyhydroxides component. The latter is considered as the real OER catalytic phase. This study advances the design of efficient and durable nonprecious bifunctional catalysts for rechargeable zinc-air batteries.

Automated summary

A three-dimensional ordered macroporous N-doped trimetal sulfides bifunctional catalyst has been developed for oxygen evolution reaction and oxygen reduction reaction in rechargeable zinc-air batteries. The catalyst exhibits excellent bifunctional catalytic activity, improving the performance and cycle life of the batteries.