The development of cost-effective electrocatalysts with high efficiency and long durability for hydrogen evolution reaction(HER)remains a great challenge in the field of water splitting.Herein,we design an ultrafine a...The development of cost-effective electrocatalysts with high efficiency and long durability for hydrogen evolution reaction(HER)remains a great challenge in the field of water splitting.Herein,we design an ultrafine and highly dispersed Ru nanoparticles stabilized on porous V_(8)C_(7)/C matrix via pyrolysis of the metal-organic frameworks V-BDC(BDC:1,4-benzenedicarboxylate).The obtained Ru-V_(8)C_(7)/C composite exhibits excellent HER performance in all p H ranges.At the overpotential of 40 mV,its mass activity is about 1.9,4.1 and 9.4 times higher than that of commercial Pt/C in acidic,neutral and alkaline media,respectively.Meanwhile,Ru-V_(8)C_(7)/C shows the remarkably high stability in all p H ranges which,in particular,can maintain the current density of 10 m A cm^(-2)for over 150 h in 1.0 mol L^(-1)phosphate buffer saline(PBS).This outstanding HER performance can be attributed to the high intrinsic activity of Ru species and their strong interface interactions to the V_(8)C_(7)/C substrate.The synergistic effect of abundant active sites on the surface and the formed Ru-C-V units at the interface promotes the adsorption of reaction intermediates and the release of active sites,contributing the fast HER kinetics.This work provides a reference for developing versatile and robust HER catalysts by surface and interface regulation for pH tolerance.展开更多
Recent advances in the design and development of magnetic storage devices have led to an enormous interest in materials with perpendicular magnetic anisotropy(PMA)property.The past decade has witnessed a huge growth i...Recent advances in the design and development of magnetic storage devices have led to an enormous interest in materials with perpendicular magnetic anisotropy(PMA)property.The past decade has witnessed a huge growth in the development of flexible devices such as displays,circuit boards,batteries,memories,etc.since they have gradually made an impact on people’s lives.Thus,the integration of PMA materials with flexible substrates can benefit the development of flexible magnetic devices.In this study,we developed a heteroepitaxy of BaFe_(12)O_(19)(BaM)/muscovite which displays both mechanical flexibility and PMA property.The particular PMA property was characterized by vibrating sample magnetometer,magnetic force microscopy,and x-ray absorption spectroscopy.To quantify the PMA property of the system,the intrinsic magnetic anisotropy energy density of~2.83 Merg cm−3 was obtained.Furthermore,the heterostructure exhibits robust PMA property against severe mechanical bending.The findings of this study on the BaM/muscovite heteroepitaxy have several important implications for research in next-generation flexible magnetic recording devices and actuators.展开更多
基金supported by the Overseas High-level Talents Plan of China and Guangdong Provincethe 100 Talents Plan Foundation of Sun Yat-sen University+4 种基金the Fundamental Research Funds for the Central Universitiesthe Program for Guangdong Introducing Innovative and Entrepreneurial Teams(2017ZT07C069)the National Natural Science Foundation of China(22075321,21821003,21890380,and 22375223)the Guangdong Basic Research Center of Excellence for Functional Molecular Engineeringthe Natural Science Foundation of Guangdong Province(2021A1515010068)。
文摘The development of cost-effective electrocatalysts with high efficiency and long durability for hydrogen evolution reaction(HER)remains a great challenge in the field of water splitting.Herein,we design an ultrafine and highly dispersed Ru nanoparticles stabilized on porous V_(8)C_(7)/C matrix via pyrolysis of the metal-organic frameworks V-BDC(BDC:1,4-benzenedicarboxylate).The obtained Ru-V_(8)C_(7)/C composite exhibits excellent HER performance in all p H ranges.At the overpotential of 40 mV,its mass activity is about 1.9,4.1 and 9.4 times higher than that of commercial Pt/C in acidic,neutral and alkaline media,respectively.Meanwhile,Ru-V_(8)C_(7)/C shows the remarkably high stability in all p H ranges which,in particular,can maintain the current density of 10 m A cm^(-2)for over 150 h in 1.0 mol L^(-1)phosphate buffer saline(PBS).This outstanding HER performance can be attributed to the high intrinsic activity of Ru species and their strong interface interactions to the V_(8)C_(7)/C substrate.The synergistic effect of abundant active sites on the surface and the formed Ru-C-V units at the interface promotes the adsorption of reaction intermediates and the release of active sites,contributing the fast HER kinetics.This work provides a reference for developing versatile and robust HER catalysts by surface and interface regulation for pH tolerance.
基金supported by the Ministry of Science and Technology,Taiwan(grant No.MOST 110-2634-F-009-026)the Center for Emergent Functional Matter Science of National Yang Ming Chiao Tung University from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education(MOE)in Taiwan.NY and TK were supported by JSPS KAKENHI(grant Nos.JP19H05823 and JP21H04436)Rong Huang was supported by the National Natural Science Foundation of China(Grant No.61974042).
文摘Recent advances in the design and development of magnetic storage devices have led to an enormous interest in materials with perpendicular magnetic anisotropy(PMA)property.The past decade has witnessed a huge growth in the development of flexible devices such as displays,circuit boards,batteries,memories,etc.since they have gradually made an impact on people’s lives.Thus,the integration of PMA materials with flexible substrates can benefit the development of flexible magnetic devices.In this study,we developed a heteroepitaxy of BaFe_(12)O_(19)(BaM)/muscovite which displays both mechanical flexibility and PMA property.The particular PMA property was characterized by vibrating sample magnetometer,magnetic force microscopy,and x-ray absorption spectroscopy.To quantify the PMA property of the system,the intrinsic magnetic anisotropy energy density of~2.83 Merg cm−3 was obtained.Furthermore,the heterostructure exhibits robust PMA property against severe mechanical bending.The findings of this study on the BaM/muscovite heteroepitaxy have several important implications for research in next-generation flexible magnetic recording devices and actuators.
