Metal-organic framework(MOF)nanostructures have emerged as a prominent class of materials in the advancement of electrochemical sensors.The rational design of bimetallic MOF-functionalized microelectrode is of importa...Metal-organic framework(MOF)nanostructures have emerged as a prominent class of materials in the advancement of electrochemical sensors.The rational design of bimetallic MOF-functionalized microelectrode is of importance for improv-ing the electrochemical performance but still in great challenge.In this work,the bimetallic FeCo-MOF nanostructures were assembled onto a gold disk ultramicroelectrode(Au UME,5.2μm in diameter)via an in-situ electrodeposition method,which enhanced the sensitive detection of epinephrine(EP).The in-situ electrodeposited FeCo-MOF exhibited a character-istic nanoflower-like morphology and was uniformly dispersed on the Au UME.The FeCo-MOF/Au UME demonstrated excellent electrochemical performance on the detection of EP with a high sensitivity of 36.93μA·μmol^(-1)·L·cm^(-2)and a low detection limit of 1.28μmol·L^(-1).It can be attributed to the nonlinear diffusion of EP onto the ultra-micro working substrate,coupled with synergistical catalytic activity of the bimetallic Fe,Co within MOF structure.Furthermore,the FeCo-MOF/Au UME has been successful applied to the analysis of EP in human serum samples,yielding high recovery rates.These results not only contribute to the expansion of the research area of electrochemical sensors,but also provide novel insights and directions into the development of high-performance MOF-based electrochemical sensors.展开更多
Magnesium hydride(MgH_(2))is an important material for hydrogen(H_(2))storage and transportation owing to its high capacity and reversibility.However,its intrinsic properties have considerably limited its industrial a...Magnesium hydride(MgH_(2))is an important material for hydrogen(H_(2))storage and transportation owing to its high capacity and reversibility.However,its intrinsic properties have considerably limited its industrial application.In this study,the NiFe-800 catalyst as metal-organic framework(MOF)derivative was first utilized to promote the intrinsic properties of MgH_(2).Compared to pure MgH_(2),which releases1.24 wt%H_(2)in 60 min at 275℃,the MgH_(2)-10 NiFe-800 composite releases 5.85 wt%H_(2)in the same time.Even at a lower temperature of 250℃,the MgH_(2)-10 NiFe-800 composite releases 3.57 wt%H_(2),surpassing the performance of pure MgH_(2)at 275℃.Correspondingly,while pure MgH_(2)absorbs 2.08 wt%H_(2)in60 min at 125℃,the MgH_(2)-10 NiFe-800 composite absorbs 5.35 wt%H_(2)in just 1 min,Remarkably,the MgH_(2)-10 NiFe-800 composite absorbs 2.27 wt%H_(2)in 60 min at 50℃and 4.64 wt%H_(2)at 75℃.This indicates that MgH_(2)-10 NiFe-800 exhibits optimum performance with excellent kinetics at low temperatures.Furthermore,the capacity of the MgH_(2)-10 NiFe-800 composite remains largely stable after 10cycles.Moreover,the Mg_(2)Ni/Mg_(2)NiH_(4)acts as a"hydrogen pump",providing effective diffusion channels that enhance the kinetic process of the composite during cycling.Additionally,Fe0facilitates electron transfer and creates hydrogen diffusion channels and catalytic sites.Finally,carbon(C)effectively prevents particle agglomeration and maintains the cyclic stability of the composites.Consequently,the synergistic effects of Mg_(2)Ni/Mg_(2)NiH_(4),Fe^(0),and C considerably improve the kinetic properties and cycling stability of MgH_(2).This work offers an effective and valuable approach to improving the hydrogen storage efficiency in the commercial application of MgH_(2).展开更多
基金support from the National Key Research and Development Program of China(2021YFB3201400,2021YFB3201401,2020YFC1908602)the National Natural Science Foundation of China(21904001 and 61774159)+1 种基金the Anhui Provincial Natural Science Foundation(2008085QF288)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Anhui Province(2020LCX032).
文摘Metal-organic framework(MOF)nanostructures have emerged as a prominent class of materials in the advancement of electrochemical sensors.The rational design of bimetallic MOF-functionalized microelectrode is of importance for improv-ing the electrochemical performance but still in great challenge.In this work,the bimetallic FeCo-MOF nanostructures were assembled onto a gold disk ultramicroelectrode(Au UME,5.2μm in diameter)via an in-situ electrodeposition method,which enhanced the sensitive detection of epinephrine(EP).The in-situ electrodeposited FeCo-MOF exhibited a character-istic nanoflower-like morphology and was uniformly dispersed on the Au UME.The FeCo-MOF/Au UME demonstrated excellent electrochemical performance on the detection of EP with a high sensitivity of 36.93μA·μmol^(-1)·L·cm^(-2)and a low detection limit of 1.28μmol·L^(-1).It can be attributed to the nonlinear diffusion of EP onto the ultra-micro working substrate,coupled with synergistical catalytic activity of the bimetallic Fe,Co within MOF structure.Furthermore,the FeCo-MOF/Au UME has been successful applied to the analysis of EP in human serum samples,yielding high recovery rates.These results not only contribute to the expansion of the research area of electrochemical sensors,but also provide novel insights and directions into the development of high-performance MOF-based electrochemical sensors.
基金financially supported by the Natural Science Foundation of Guangdong province(2024A1515010228)the Research and demonstration application of intelligent sensing technology for lithium ion battery energy storage(SPICXJ-HTBBC-2022-01).
文摘Magnesium hydride(MgH_(2))is an important material for hydrogen(H_(2))storage and transportation owing to its high capacity and reversibility.However,its intrinsic properties have considerably limited its industrial application.In this study,the NiFe-800 catalyst as metal-organic framework(MOF)derivative was first utilized to promote the intrinsic properties of MgH_(2).Compared to pure MgH_(2),which releases1.24 wt%H_(2)in 60 min at 275℃,the MgH_(2)-10 NiFe-800 composite releases 5.85 wt%H_(2)in the same time.Even at a lower temperature of 250℃,the MgH_(2)-10 NiFe-800 composite releases 3.57 wt%H_(2),surpassing the performance of pure MgH_(2)at 275℃.Correspondingly,while pure MgH_(2)absorbs 2.08 wt%H_(2)in60 min at 125℃,the MgH_(2)-10 NiFe-800 composite absorbs 5.35 wt%H_(2)in just 1 min,Remarkably,the MgH_(2)-10 NiFe-800 composite absorbs 2.27 wt%H_(2)in 60 min at 50℃and 4.64 wt%H_(2)at 75℃.This indicates that MgH_(2)-10 NiFe-800 exhibits optimum performance with excellent kinetics at low temperatures.Furthermore,the capacity of the MgH_(2)-10 NiFe-800 composite remains largely stable after 10cycles.Moreover,the Mg_(2)Ni/Mg_(2)NiH_(4)acts as a"hydrogen pump",providing effective diffusion channels that enhance the kinetic process of the composite during cycling.Additionally,Fe0facilitates electron transfer and creates hydrogen diffusion channels and catalytic sites.Finally,carbon(C)effectively prevents particle agglomeration and maintains the cyclic stability of the composites.Consequently,the synergistic effects of Mg_(2)Ni/Mg_(2)NiH_(4),Fe^(0),and C considerably improve the kinetic properties and cycling stability of MgH_(2).This work offers an effective and valuable approach to improving the hydrogen storage efficiency in the commercial application of MgH_(2).
