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...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.展开更多
基金supported by the National Natural Science Foundation of China(no.21972010)Beijing Natural Science Foundation(no.2192039)+3 种基金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).
文摘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.
