High density lanthanum hexaboride(LaB_(6))polycrystalline with(100)preferred orientation was prepared by spark plasma sintering(SPS)using LaB_(6) nanocubes as raw materials in this work.Microstructure and thermionic e...High density lanthanum hexaboride(LaB_(6))polycrystalline with(100)preferred orientation was prepared by spark plasma sintering(SPS)using LaB_(6) nanocubes as raw materials in this work.Microstructure and thermionic electron emission property of LaB_(6) polycrystalline were investigated detailedly.The results show that the LaB_(6) polycrystalline had a relative density of 95.8%,and there was a(100)preferred orientation on its surface normal to SPS pressing direction.The work function of LaB_(6) polycrystalline normal surface was only 2.73 eV,which was almost close to the theoretical work function of LaB_(6)(100)single crystal surface.The reasons for preferential orientation of LaB_(6) polycrystalline were analyzed.展开更多
The synthesis, structure and performance of Li2Mg0.15Mn0.4Co0.45SiO4/C cathode material were studied. The Li2Mg0.15Mn0.4Co0.45SiO4/C solid solution with orthorhombic unit cell （space group Pmn21） was synthesized suc...The synthesis, structure and performance of Li2Mg0.15Mn0.4Co0.45SiO4/C cathode material were studied. The Li2Mg0.15Mn0.4Co0.45SiO4/C solid solution with orthorhombic unit cell （space group Pmn21） was synthesized successfully by combination of wet process and solid-state reaction at high temperature, and its electrochemical performance was investigated primarily. Li2Mg0.15Mn0.4Co0.45SiO4/C composite materials deliver a charge capacity of 302 mA-h/g and a discharge capacity of 171 mA.h/g in the first cycle. The discharge capacity is stabilized at about 100 mA-h/g after 10 cycles at a current density of 10 mA/g in the voltage of 1.5-4.8 V vs Li/Li^＋. The results show that Mg-substitution for the Co ions in Li2Mn0.4Co0.6SiO4 improves the stabilization of initial structure and the electrochemical nerformance.展开更多
基金Project(51902342)supported by the National Natural Science Foundation of China。
文摘High density lanthanum hexaboride(LaB_(6))polycrystalline with(100)preferred orientation was prepared by spark plasma sintering(SPS)using LaB_(6) nanocubes as raw materials in this work.Microstructure and thermionic electron emission property of LaB_(6) polycrystalline were investigated detailedly.The results show that the LaB_(6) polycrystalline had a relative density of 95.8%,and there was a(100)preferred orientation on its surface normal to SPS pressing direction.The work function of LaB_(6) polycrystalline normal surface was only 2.73 eV,which was almost close to the theoretical work function of LaB_(6)(100)single crystal surface.The reasons for preferential orientation of LaB_(6) polycrystalline were analyzed.
基金Project(10B054)supported by Scientific Research Fund of Hunan Provincial Education Department,ChinaProjects(2011GK2002,2011FJ3160)supported by the Planned Science and Technology Program of Hunan Province,China
文摘The synthesis, structure and performance of Li2Mg0.15Mn0.4Co0.45SiO4/C cathode material were studied. The Li2Mg0.15Mn0.4Co0.45SiO4/C solid solution with orthorhombic unit cell （space group Pmn21） was synthesized successfully by combination of wet process and solid-state reaction at high temperature, and its electrochemical performance was investigated primarily. Li2Mg0.15Mn0.4Co0.45SiO4/C composite materials deliver a charge capacity of 302 mA-h/g and a discharge capacity of 171 mA.h/g in the first cycle. The discharge capacity is stabilized at about 100 mA-h/g after 10 cycles at a current density of 10 mA/g in the voltage of 1.5-4.8 V vs Li/Li^＋. The results show that Mg-substitution for the Co ions in Li2Mn0.4Co0.6SiO4 improves the stabilization of initial structure and the electrochemical nerformance.
