Metalloenzymes play a crucial role in life,performing myriad functions in aqueous environments in nature.Understanding these systems’structural and functional mimics in water at ambient temperature is essential for d...Metalloenzymes play a crucial role in life,performing myriad functions in aqueous environments in nature.Understanding these systems’structural and functional mimics in water at ambient temperature is essential for developing new catalysts.Inspired by nature,we report here the synthesis of a remarkably stable formal[(L)Cu(Ⅲ)]^(+)(2)species supported by a tetradentate pseudopeptide ligand,which we then characterized by various spectroscopic techniques in water at ambient temperature and using DFT methods.Our experimental and DFT studies indicate that the observed stability is caused by hydrogen bonding of water molecules to the amide moiety of the ligand bound to the formal Cu(Ⅲ)center.The Natural Bonding Orbital(NBO)analysis indicated the best description of the oxidized species to be formal Cu(Ⅲ).The formal Cu(Ⅲ)species(2)could also be prepared by electrochemical oxidation methods in water.The generated species 2 was found to be reactive towards various phenols in H_(2)O:CH_(3)CN(1:1).The ability to stabilize formal Cu(Ⅲ)in water encouraged us to investigate the biological activity of[(L)Cu(Ⅱ)](1)in cancer cell proliferation.Studies of these metalloenzyme mimics in cells indicated that intracellular and extracellular reactive oxygen species(ROS)generation,in turn,selectively prevented the growth of liver cancer cells over other cancer cell lines and normal kidney cells.展开更多
The search for efficient,robust,and cost-effective catalysts for the hydrogen evolution reaction(HER)is highly desirable.However,the development of freshwater/seawater electrolysis for hydrogen production as a viable ...The search for efficient,robust,and cost-effective catalysts for the hydrogen evolution reaction(HER)is highly desirable.However,the development of freshwater/seawater electrolysis for hydrogen production as a viable energy conversion technology remains a challenge.Herein,a fluorine-doped Ni(OH)_(2)/Ni–B amorphous heterostructure(FNH/NB)was synthesized via simple hydrothermal,electroless plating,and alkaline etching methods.Our designed experiments demonstrate that the as-prepared catalyst benefiting from amorphous interfacial coupling and F-induced effects exhibits accelerated H_(2)O dissociation kinetics and optimized adsorption of intermediates.As a result,the FNH/NB catalyst shows high alkaline HER activity,requiring low overpotentials of 23,28,and 30 mV to drive a current density of 10 mA cm^(−2) in alkaline freshwater,simulated seawater,and real seawater,respectively.Particularly,the stability of the designed catalyst is effectively improved using a fluorine doping strategy.Specifically,FNH/NB could maintain excellent electrocatalytic performance over 50 hours at current densities of 10 and 1000 mA cm^(−2) in an alkaline solution containing KF.The current work reveals the superiority of integrating F doping and amorphous heterostructure engineering in developing efficient and robust catalysts.展开更多
基金supported by the SERB(CRG/2023/001112 and CRG/2021/004787)CSIR(01(3050)/21/EMR-II and 02(366)/19/EMR-II)+1 种基金DBT(BT/12/IYBA/2019/07)ICMR(AMR/ADHOC/296/2022-ECD-II).
文摘Metalloenzymes play a crucial role in life,performing myriad functions in aqueous environments in nature.Understanding these systems’structural and functional mimics in water at ambient temperature is essential for developing new catalysts.Inspired by nature,we report here the synthesis of a remarkably stable formal[(L)Cu(Ⅲ)]^(+)(2)species supported by a tetradentate pseudopeptide ligand,which we then characterized by various spectroscopic techniques in water at ambient temperature and using DFT methods.Our experimental and DFT studies indicate that the observed stability is caused by hydrogen bonding of water molecules to the amide moiety of the ligand bound to the formal Cu(Ⅲ)center.The Natural Bonding Orbital(NBO)analysis indicated the best description of the oxidized species to be formal Cu(Ⅲ).The formal Cu(Ⅲ)species(2)could also be prepared by electrochemical oxidation methods in water.The generated species 2 was found to be reactive towards various phenols in H_(2)O:CH_(3)CN(1:1).The ability to stabilize formal Cu(Ⅲ)in water encouraged us to investigate the biological activity of[(L)Cu(Ⅱ)](1)in cancer cell proliferation.Studies of these metalloenzyme mimics in cells indicated that intracellular and extracellular reactive oxygen species(ROS)generation,in turn,selectively prevented the growth of liver cancer cells over other cancer cell lines and normal kidney cells.
基金The authors are grateful to Guangxi Science and Technology Program[No.Guike AD23026107]Natural Science Foundation of Guangxi Province of China[No.2024GXNSFBA010234]the National Natural Science Foundation of China[No.22062002,22265002]for financial support.
文摘The search for efficient,robust,and cost-effective catalysts for the hydrogen evolution reaction(HER)is highly desirable.However,the development of freshwater/seawater electrolysis for hydrogen production as a viable energy conversion technology remains a challenge.Herein,a fluorine-doped Ni(OH)_(2)/Ni–B amorphous heterostructure(FNH/NB)was synthesized via simple hydrothermal,electroless plating,and alkaline etching methods.Our designed experiments demonstrate that the as-prepared catalyst benefiting from amorphous interfacial coupling and F-induced effects exhibits accelerated H_(2)O dissociation kinetics and optimized adsorption of intermediates.As a result,the FNH/NB catalyst shows high alkaline HER activity,requiring low overpotentials of 23,28,and 30 mV to drive a current density of 10 mA cm^(−2) in alkaline freshwater,simulated seawater,and real seawater,respectively.Particularly,the stability of the designed catalyst is effectively improved using a fluorine doping strategy.Specifically,FNH/NB could maintain excellent electrocatalytic performance over 50 hours at current densities of 10 and 1000 mA cm^(−2) in an alkaline solution containing KF.The current work reveals the superiority of integrating F doping and amorphous heterostructure engineering in developing efficient and robust catalysts.
