Cooperative dual-atomic-site catalysis enables highly efficient oxygen reduction reaction and long-life Zn-air battery

Rational design and synthesis of electrocatalysts that efficiently catalyze oxygen reduction reaction (ORR) is critical to the development of fuel cells and Zn-air battery (ZAB). However, it remains the most significant obstacle due to the potential-dependent energy barrier for oxygen intermediates (OOH*, O* and OH*) adsorption/desorption on single atom active sites. Here we report a novel deprotonated 2-aminoterephthalic acid (H 2 BDC-NH 2 ) coordinated compound precursor-mediated method for synthesizing dual-atomic-site electrocatalyst (FeNi-DSAs/NSs) that facilitate ORR kinetics. The experimental and theoretical calculation results verify that the Fe and Ni cooperative effect induces a distinct negative shift of the d-band center for Fe, thereby reducing the adsorption strength of oxygen intermediates on Fe sites. Additionally, the introduced Ni species decrease the energy barrier of the rate-determining step (RDS), thus accelerating catalytic ORR process. Consequently, FeNi-DSAs/NSs exhibits excellent ORR performance in 0.1 M KOH solution with a very large half-wave potential (E 1/2 ) of 0.92 V and a remarkable lifespan, maintaining stability for over 90 h. In aqueous Zn-air battery (A-ZAB), this electrocatalyst enables a high-power density (254 mW cm −2 ), and can maintain stable charge/discharge for more than 1600 h with negligible potential gap fluctuation. Notably, for quasi-solid-state Zn-air battery (QSS-ZAB) with FeNi-DSAs/NSs, it shows excellent cycle life for over 110 h and high energy conversion efficiency at 0.5, 1.0, and 2.0 mA cm −2 , respectively. This work not only provides a novel design strategy for excellent catalysts, but also highlights the potential application of non-precious metal electrocatalysts in renewable energy conversion and storage apparatuses.