As a general problem in the field of batteries,materials produced on a large industrial scale usually possess unsatisfactory electrochemical performances.Among them,manganese-based aqueous rechargeable zinc-ion batter...As a general problem in the field of batteries,materials produced on a large industrial scale usually possess unsatisfactory electrochemical performances.Among them,manganese-based aqueous rechargeable zinc-ion batteries(ARZBs)have been emerging as promising large-scale energy storage systems owing to their high energy densities,low manufacturing cost and intrinsic high safety.However,the direct application of industrial-scale Mn2O3(MO)cathode exhibits poor electrochemical performance especially at high current rates.Herein,a highly reversible Mn-based cathode is developed from the industrial-scale MO by nitridation and following electrochemical oxidation,which triples the ion diffusion rate and greatly promotes the charge transfer.Notably,the cathode delivers a capacity of 161 m Ah g^(-1) at a high current density of 10 A g^(-1),nearly-three times the capacity of pristine MO(60 m Ah g^(-1)).Impressive specific capacity(243.4 m Ah g^(-1))is obtained without Mn^(2+) additive added in the electrolyte,much superior to the pristine MO(124.5 m Ah g^(-1)),suggesting its enhanced reaction kinetics and structural stability.In addition,it possesses an outstanding energy output of 368.4 Wh kg^(-1) at 387.8 W kg^(-1),which exceeds many of reported cathodes in ARZBs,providing new opportunities for the large-scale application of highperformance and low-cost ARZBs.展开更多
Atomic noble metals stand as one of the most advanced catalysts because of their unique properties and interaction with the reactants.However,due to their high activity,noble atomic catalysts tend to aggregate and dea...Atomic noble metals stand as one of the most advanced catalysts because of their unique properties and interaction with the reactants.However,due to their high activity,noble atomic catalysts tend to aggregate and deactivate in practical application.Moreover,supports aimed to disperse these atomic catalysts often suffer from weak confinement and poor porosity,thus limited the catalytic efficiency of noble atoms.Here,we report the facile encapsulation of atomic noble catalyst in cheap cerous metal-organic framework(Ce-MOF)crystals to create a robust catalyst that could deliver high catalytic performance for the reduction of 4-nitrophenol without decay in long-term cycling test.Specifically,Au atoms encapsulated in Ce-MOF exhibited ultrahigh turnover frequency(TOF)of 131 min−1 for the reduction of 4-nitrophenol in minutes,consuming only 10%precious metals compared with state-of-the-art catalysts operated under same condition.展开更多
基金supports from the National Natural Science Foundation of China(No.21805063)the Natural Science Foundation of Guangdong Province for Distinguished Young Scholars(No.2018B030306022)+2 种基金the Project of International Science and Technology Cooperation in Guangdong Province(No.2020A0505100016)the Shenzhen Sauvage Nobel Laureate Laboratory for Smart Materialsthe Shenzhen Science and Technology Program(Nos.KQTD20200820113045083,ZDSYS20190902093220279)。
文摘As a general problem in the field of batteries,materials produced on a large industrial scale usually possess unsatisfactory electrochemical performances.Among them,manganese-based aqueous rechargeable zinc-ion batteries(ARZBs)have been emerging as promising large-scale energy storage systems owing to their high energy densities,low manufacturing cost and intrinsic high safety.However,the direct application of industrial-scale Mn2O3(MO)cathode exhibits poor electrochemical performance especially at high current rates.Herein,a highly reversible Mn-based cathode is developed from the industrial-scale MO by nitridation and following electrochemical oxidation,which triples the ion diffusion rate and greatly promotes the charge transfer.Notably,the cathode delivers a capacity of 161 m Ah g^(-1) at a high current density of 10 A g^(-1),nearly-three times the capacity of pristine MO(60 m Ah g^(-1)).Impressive specific capacity(243.4 m Ah g^(-1))is obtained without Mn^(2+) additive added in the electrolyte,much superior to the pristine MO(124.5 m Ah g^(-1)),suggesting its enhanced reaction kinetics and structural stability.In addition,it possesses an outstanding energy output of 368.4 Wh kg^(-1) at 387.8 W kg^(-1),which exceeds many of reported cathodes in ARZBs,providing new opportunities for the large-scale application of highperformance and low-cost ARZBs.
基金S.Guo and H.Yuan contribute equally to this study.We thank the supports from National key R&D program of China(No.2018YFB1107700)National Natural Science Foundation of China(No.51906180).
文摘Atomic noble metals stand as one of the most advanced catalysts because of their unique properties and interaction with the reactants.However,due to their high activity,noble atomic catalysts tend to aggregate and deactivate in practical application.Moreover,supports aimed to disperse these atomic catalysts often suffer from weak confinement and poor porosity,thus limited the catalytic efficiency of noble atoms.Here,we report the facile encapsulation of atomic noble catalyst in cheap cerous metal-organic framework(Ce-MOF)crystals to create a robust catalyst that could deliver high catalytic performance for the reduction of 4-nitrophenol without decay in long-term cycling test.Specifically,Au atoms encapsulated in Ce-MOF exhibited ultrahigh turnover frequency(TOF)of 131 min−1 for the reduction of 4-nitrophenol in minutes,consuming only 10%precious metals compared with state-of-the-art catalysts operated under same condition.
