Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly acti...Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly active ORR electrocatalysts with superior kinetics hinders progress in this field.Herein,we report the Fe/Ni dual single-atomic sites anchored by commercial carbon black(Fe/Ni-N/CB)using rigid ligand confined and high-temperature shock(HTS)strategy in less than 0.5 s.Theoretical calculation reveals that singleatomic Fe is the real active site.Single-atomic Fe and Ni species in Fe/Ni-N/CB synergistically accelerate the kinetics of ORR by reducing the energy barrier of the rate-determining step.A large half-wave potential(E_(1/2))of 0.907 V is achieved in 0.1 M KOH aqueous solution.The assembled aqueous Zn-air battery(A-ZAB)with Fe/Ni-N/CB cathode presents remarkable charge-discharge cycling stability for over 650 h without voltage gap degradation.The quasi-solid-state Zn-air battery(QSS-ZAB)exhibits excellent reversibility over a 150-h operation at 0.5 mA·cm^(-2) with negligible energy conversion efficiency recession.Impressively,Fe/Ni-N/CB||RuO_(2)chloralkali flow cell exhibits a low cell voltage of 1.60 V at a large current density of 300 mA·cm^(-2) at 80℃,and demonstrates exceptional durability with 7% current density decay over 150 h of continuous operation at 100 mA·cm^(-2).Fe/Ni-N/CB||RuO_(2)achieves near-ideal caustic current efficiency(~97.2%)at the current density of 300 mA·cm^(-2).This work provides a rapid and economical synthesis technique for the synthesis of catalysts at the atomic scale while demonstrating significant potential for application in energy-saving chlor-alkali electrolyzer.展开更多
基金supported financially by the National Natural Science Foundation of China(No.52172208)Taishan Scholar Young Talent Program(No.tsqn202306216)Shandong Excellent Young Scientists Fund Program(Overseas,2023HWYQ‑091).
文摘Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly active ORR electrocatalysts with superior kinetics hinders progress in this field.Herein,we report the Fe/Ni dual single-atomic sites anchored by commercial carbon black(Fe/Ni-N/CB)using rigid ligand confined and high-temperature shock(HTS)strategy in less than 0.5 s.Theoretical calculation reveals that singleatomic Fe is the real active site.Single-atomic Fe and Ni species in Fe/Ni-N/CB synergistically accelerate the kinetics of ORR by reducing the energy barrier of the rate-determining step.A large half-wave potential(E_(1/2))of 0.907 V is achieved in 0.1 M KOH aqueous solution.The assembled aqueous Zn-air battery(A-ZAB)with Fe/Ni-N/CB cathode presents remarkable charge-discharge cycling stability for over 650 h without voltage gap degradation.The quasi-solid-state Zn-air battery(QSS-ZAB)exhibits excellent reversibility over a 150-h operation at 0.5 mA·cm^(-2) with negligible energy conversion efficiency recession.Impressively,Fe/Ni-N/CB||RuO_(2)chloralkali flow cell exhibits a low cell voltage of 1.60 V at a large current density of 300 mA·cm^(-2) at 80℃,and demonstrates exceptional durability with 7% current density decay over 150 h of continuous operation at 100 mA·cm^(-2).Fe/Ni-N/CB||RuO_(2)achieves near-ideal caustic current efficiency(~97.2%)at the current density of 300 mA·cm^(-2).This work provides a rapid and economical synthesis technique for the synthesis of catalysts at the atomic scale while demonstrating significant potential for application in energy-saving chlor-alkali electrolyzer.