摘要
Single-atom catalysts with precise structure and tunable coordination nature provide opportunities for developing novel catalytic centers and understanding reaction mechanisms.Herein,hollow Co_(9)S_(8)polyhedrons with lattice-confined Ru single atoms(Ru-Co_(9)S_(8))are fabricated.Aberration-corrected scanning transmission electron microscopy and X-ray absorption spectroscopy verify the isolated Ru atoms are confined in Co_(9)S_(8)to form Co-S-Ru catalytic centers.Theoretical calculations indicate that the oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)energy barriers are extensively reduced,the d-band center of Co_(9)S_(8)downshifts from the Fermi level,therefore boosting the desorption of O-containing intermediates.Consequently,the Ru-Co_(9)S_(8)exhibits an ultralow overpotential of 163 mV at 10 mA·cm^(−2)for OER and could catalyze a rechargeable Zn-air battery with a high-power density of 92.0 mW·cm^(−2).This work provides a promising approach for designing novel bifunctional catalytic active centers for energy conversion.
基金
the National Natural Science Foundation of China(No.21902189)
Key Scientific Research Projects of Universities in Henan Province(No.21A150062)
Young Backbone Teacher of Zhongyuan University of Technology(No.2020XQG09)
the Fundamental Research Funds of Zhongyuan University of Technology(No.K2020YY003).
