摘要
Demand for ammonia continues to increase to sustain the growing global population.The direct electrochemical N2 reduction reaction(NRR)powered by renewable electricity offers a promising carbon-neutral and sustainable strategy for manufacturing NH3,yet achieving this remains a grand challenge.Here,we report a synergistic strategy to promote ambient NRR for ammonia production by tuning the Te vacancies(VTe)and surface hydrophobicity of two-dimensional TaTe_(2)nanosheets.Remarkable NH3 faradic efficiency of up to 32.2%is attained at a mild overpotential,which is largely maintained even after 100 h of consecutive electrolysis.Isotopic labeling validates that the N atoms of formed NH4+originate from N2.In situ X-ray diffraction indicates preservation of the crystalline structure of TaTe_(2)during NRR.Further density functional theory calculations reveal that the potential-determining step(PDS)is*NH_(2)+(H^(+)+e^(-))/NH3 on VTe-TaTe_(2)compared with that of*+N2+(H^(+)+e^(-))/*N-NH on TaTe_(2).We identify that the edge plane of TaTe_(2)and VTe serve as the main active sites for NRR.The free energy change at PDS on VTe-TaTe_(2)is comparable with the values at the top of the NRR volcano plots on various transition metal surfaces.
基金
supported by the National Natural Science Foundation of China(no.21972010)
Beijing Natural Science Foundation(no.2192039)
the State Key Laboratory of Organic-Inorganic Composites(no.oic201901001)
Beijing University of Chemical Technology(XK180301)
NRF Korea(NRF-2016M3D1A1021147)
the facilities of the DCCEM,at the Materials Department,Oxford(EP/R010145/1).
