Two dimensional PdRuMoFeCo multi-component metallene for rechargeable Zn–air batteries with high performance

Abstract

Developing high-performance bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is a key to address the limitations of conventional catalysts for rechargeable Zn–air batteries (ZABs). Herein, two-dimensional PdRuMoFeCo multi-component alloy metallene synthesized via a one-pot method exhibits exceptional performance in rechargeable ZABs. First, PdRuMoFeCo metallene not only shows a more positive half-wave potential of 0.893 V (vs. RHE), a lower Tafel slope of 18.71 mV dec⁻¹ and a higher mass activity of 159.18 mA mg⁻¹ PGM than commercial Pt/C for the ORR, but also exhibits a lower potential difference (ΔE = 0.80 V) between the E_{j=10 mA cm⁻²} for the OER and E_1/2 for the ORR than commercial Pt/C (ΔE = 1.02 V), indicating the excellent bifunctional activity for the OER and ORR. The enhanced activity could be attributed to the synergistic interplay among the multi-metallic components and the unique metallene architecture. When integrated into ZABs, the PdRuMoFeCo metallene delivers a high peak power density of 175.3 mW cm⁻² (twice that of Pt/C), an energy density of 787.6 mAh g⁻¹, and remarkable cycling stability. This work not only propels the development of metallene-based electrocatalysts, but also provides a strategic framework for designing multi-component nanomaterials for next-generation energy storage systems.