将共沉淀法和固相法相结合,将Si 4+掺杂到LiNi 0.5 Mn 0.5 O 2中,合成LiNi 0.5-x Si x Mn 0.5 O 2(0≤x≤0.08)正极材料。通过XRD及精修、等离子体发射光谱(ICP)、SEM和透射电子显微镜(TEM)等方法,对合成材料的结构、成分和形貌进行分析...将共沉淀法和固相法相结合,将Si 4+掺杂到LiNi 0.5 Mn 0.5 O 2中,合成LiNi 0.5-x Si x Mn 0.5 O 2(0≤x≤0.08)正极材料。通过XRD及精修、等离子体发射光谱(ICP)、SEM和透射电子显微镜(TEM)等方法,对合成材料的结构、成分和形貌进行分析。Si 4+掺杂不仅可降低材料的锂镍混排程度,还能增强结构稳定性,且不会改变材料的形貌。以40 mA/g(0.2 C)的电流在2.5~4.5 V充放电,LiNi 0.47 Si 0.03 Mn 0.5 O 2(x=0.03)正极材料具有最好的电化学性能,不仅比容量(149.25 mAh/g)较未掺杂材料(125.44 mAh/g)提高20%,而且容量保持率在120次循环后也提高了7.7%。Si 4+掺杂能降低材料的锂镍混排程度,有利于Li+的迁移;能提高材料的结构稳定性,抑制电压的下降并减轻极化。展开更多
Spin pumping at the Co2FeAl0.5Si0.5/Pt and Pt/Co2FeAl0.5Si0.5 interfaces has been studied by ferromagnetic resonance technology(FMR). The spin mixing conductance of the Co2FeAl0.5Si0.5/Pt and Pt/Co2FeAl0.5Si0.5 interf...Spin pumping at the Co2FeAl0.5Si0.5/Pt and Pt/Co2FeAl0.5Si0.5 interfaces has been studied by ferromagnetic resonance technology(FMR). The spin mixing conductance of the Co2FeAl0.5Si0.5/Pt and Pt/Co2FeAl0.5Si0.5 interfaces was determined to be 3.7×1019m 2and 2.1×1019m 2 by comparing the Gilbert damping in a Co2FeAl0.5Si0.5single film, Co2FeAl0.5Si0.5/Pt bilayer film and a Pt/Co2FeAl0.5Si0.5/Pt trilayer film. Spin pumping is more efficient in the Co2FeAl0.5Si0.5/Pt bilayer film than in permalloy/Pt bilayer film.展开更多
Magnetic entropy change (△SM) and refrigerant capacity (RC) of Ce6Ni2Si3-type Gd6Co1.67Si2.5Geo.5 compounds have been investigated. The Gd6Col.67Si2.5Geo.5 undergoes a reversible second-order phase transition at ...Magnetic entropy change (△SM) and refrigerant capacity (RC) of Ce6Ni2Si3-type Gd6Co1.67Si2.5Geo.5 compounds have been investigated. The Gd6Col.67Si2.5Geo.5 undergoes a reversible second-order phase transition at the Curie temperature Tc = 296 K. The high saturation magnetization leads to a large ASM and the maximal value of △SM is found to be 5.9 J/kg. K around TC for a field change of 0-5 T. A broad distribution of the △SM peak is observed and the full width at half maximum of the △SM peak is about 101 K under a magnetic field of 5 T. The large RC is found around TC and its value is 424 J/kg.展开更多
In this study,(100)-oriented growth of Ba_(0.5)Sr_(0.5)TiO_3(BST)/LaNiO_3(LNO) stacks was obtained on Pt(111)/SiO_2/Si substrates by r.f.magnetron sputtering.The orientation of the subsequently deposited Ba_(0.5)Sr_(0...In this study,(100)-oriented growth of Ba_(0.5)Sr_(0.5)TiO_3(BST)/LaNiO_3(LNO) stacks was obtained on Pt(111)/SiO_2/Si substrates by r.f.magnetron sputtering.The orientation of the subsequently deposited Ba_(0.5)Sr_(0.5)TiO_3 thin film was strongly affected by the LNO under layer,and the BST thin film deposited on the(100)LNO-coated Si substrate was also found to have a significant(100)-oriented texture.Effects of LNO interlayer on the dielectric properties of BST thin films were investigated.As a result,the tunability of BST thin film was greatly improved with the insertion of(100)-oriented LNO under layer with proper thickness.展开更多
文摘将共沉淀法和固相法相结合,将Si 4+掺杂到LiNi 0.5 Mn 0.5 O 2中,合成LiNi 0.5-x Si x Mn 0.5 O 2(0≤x≤0.08)正极材料。通过XRD及精修、等离子体发射光谱(ICP)、SEM和透射电子显微镜(TEM)等方法,对合成材料的结构、成分和形貌进行分析。Si 4+掺杂不仅可降低材料的锂镍混排程度,还能增强结构稳定性,且不会改变材料的形貌。以40 mA/g(0.2 C)的电流在2.5~4.5 V充放电,LiNi 0.47 Si 0.03 Mn 0.5 O 2(x=0.03)正极材料具有最好的电化学性能,不仅比容量(149.25 mAh/g)较未掺杂材料(125.44 mAh/g)提高20%,而且容量保持率在120次循环后也提高了7.7%。Si 4+掺杂能降低材料的锂镍混排程度,有利于Li+的迁移;能提高材料的结构稳定性,抑制电压的下降并减轻极化。
基金Project supported by the National Basic Research Program of China(Grant No.2012CB932702)the National Natural Science Foundation of China(Grant Nos.51271020,51071022,and 11174031)+2 种基金the Program for Changjiang Scholars and Innovative Research Team in University,China(PCSIRT)the Beijing Nova Program,China(Grant No.2011031)the Fundamental Research Funds for the Central Universities of Ministry of Education of China
文摘Spin pumping at the Co2FeAl0.5Si0.5/Pt and Pt/Co2FeAl0.5Si0.5 interfaces has been studied by ferromagnetic resonance technology(FMR). The spin mixing conductance of the Co2FeAl0.5Si0.5/Pt and Pt/Co2FeAl0.5Si0.5 interfaces was determined to be 3.7×1019m 2and 2.1×1019m 2 by comparing the Gilbert damping in a Co2FeAl0.5Si0.5single film, Co2FeAl0.5Si0.5/Pt bilayer film and a Pt/Co2FeAl0.5Si0.5/Pt trilayer film. Spin pumping is more efficient in the Co2FeAl0.5Si0.5/Pt bilayer film than in permalloy/Pt bilayer film.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11004204 and 51001114), the Knowledge Inno- vation Project of the Chinese Academy of Sciences, and the National Basic Research Program of China (Grant No. 2006CB601101).
文摘Magnetic entropy change (△SM) and refrigerant capacity (RC) of Ce6Ni2Si3-type Gd6Co1.67Si2.5Geo.5 compounds have been investigated. The Gd6Col.67Si2.5Geo.5 undergoes a reversible second-order phase transition at the Curie temperature Tc = 296 K. The high saturation magnetization leads to a large ASM and the maximal value of △SM is found to be 5.9 J/kg. K around TC for a field change of 0-5 T. A broad distribution of the △SM peak is observed and the full width at half maximum of the △SM peak is about 101 K under a magnetic field of 5 T. The large RC is found around TC and its value is 424 J/kg.
基金National Natural Science Foundation of China(61361008)National Key Basic Research Development Program of China("973" Program)(2010CB635112)Graduate Innovation Special Fund of Jiangxi Province(YC2016-B007)
基金the National Key Lab of Nano/Micro Fabrication Technology(No.9140C 790310060C79)the National Natural Science Foundation of China(No.60701012)
文摘In this study,(100)-oriented growth of Ba_(0.5)Sr_(0.5)TiO_3(BST)/LaNiO_3(LNO) stacks was obtained on Pt(111)/SiO_2/Si substrates by r.f.magnetron sputtering.The orientation of the subsequently deposited Ba_(0.5)Sr_(0.5)TiO_3 thin film was strongly affected by the LNO under layer,and the BST thin film deposited on the(100)LNO-coated Si substrate was also found to have a significant(100)-oriented texture.Effects of LNO interlayer on the dielectric properties of BST thin films were investigated.As a result,the tunability of BST thin film was greatly improved with the insertion of(100)-oriented LNO under layer with proper thickness.