通过高温固相法合成了BaZr 1-x Sm x O 3-δ(x=0.05,0.1,0.15,0.2)电解质材料,并对材料的物相结构进行了XRD表征。分别在空气和4%H 2O/H 2中,温度范围为500~800℃下,通过电化学工作站测试了该电解质材料的电学性能。研究发现,稀土元素S...通过高温固相法合成了BaZr 1-x Sm x O 3-δ(x=0.05,0.1,0.15,0.2)电解质材料,并对材料的物相结构进行了XRD表征。分别在空气和4%H 2O/H 2中,温度范围为500~800℃下,通过电化学工作站测试了该电解质材料的电学性能。研究发现,稀土元素Sm的掺杂对BaZrO 3电解质材料的电学性能有重大影响,当Sm元素的掺杂量为0.15时,电解质的电导率达到最大值。结果表明,Sm的掺杂可以有效提高BaZrO 3电解质材料的电导率。展开更多
Nanocrystalline and amorphous La_(2–x)Sm_xMg_(16)Ni+200wt.% Ni(x=0, 0.1, 0.2, 0.3, 0.4) alloys were prepared by mechanical milling technology. The structures of as-cast and milled alloys were investigated by X...Nanocrystalline and amorphous La_(2–x)Sm_xMg_(16)Ni+200wt.% Ni(x=0, 0.1, 0.2, 0.3, 0.4) alloys were prepared by mechanical milling technology. The structures of as-cast and milled alloys were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). Electrochemical performance of the alloy was studied by using an automatic galvanostatic system. The electrochemical impedance spectra(EIS) and Tafel polarization curves were measured by electrochemical workstation. The results indicated that the structures of the as-cast and milled alloys presented a multiphase structure with nanocrystalline and amorphous phase, moreover, transforming from nanocrystalline to amorphous phase with Sm doping. With the increase of Sm content, the maximum discharge capacity of the alloy was decreased from 922.6 to 649.1 m Ah/g, the high-rate discharge ability(HRD) was decreased, the cycle stability was strengthened, and the alloy exhibited excellent electrochemical kinetics. In addition, the charge-transfer resistance(R_(ct)) of alloy was lessened from 0.05874 to 0.02953 ? and the limiting current density(I_L) was descended from 2.08366 to 1.04592 A/g with increasing Sm content.展开更多
The effect of Dy and Sm doping on microstructure and electric properties of bismuth titanate ceramics were investigated by means of XRD, SEM and AFM. The results showed that the grain growth habit was anisotropy of BI...The effect of Dy and Sm doping on microstructure and electric properties of bismuth titanate ceramics were investigated by means of XRD, SEM and AFM. The results showed that the grain growth habit was anisotropy of BIT ceramics doped with Dy, Sm at a concentration range of 0.5%~2.5%. However, c-axis decreased more obviously with increasing dopant concentration of Sm-doped sample than Dy-doped sample. As a result, the shape of grains of Sm-doped sample were granular, in contrast with Dy-doped sample with template particles. The grain size of Sm-doped sample decreased significantly, which led to a large dielectric constant and remanent polarization.展开更多
In this article,the Sm-doping single crystals Ca1-xSmxFe2As2(x = 0 0.2) were prepared by the Ca As flux method,and followed by a rapid quenching treatment after the high temperature growth.The samples were character...In this article,the Sm-doping single crystals Ca1-xSmxFe2As2(x = 0 0.2) were prepared by the Ca As flux method,and followed by a rapid quenching treatment after the high temperature growth.The samples were characterized by structural,resistive,and magnetic measurements.The successful Sm-substitution was revealed by the reduction of the lattice parameter c,due to the smaller ionic radius of Sm3+than Ca2+.Superconductivity was observed in all samples with onset Tc varying from 27 K to 44 K upon Sm-doping.The coexistence of a collapsed phase transition and the superconducting transition was found for the lower Sm-doping samples.Zero resistivity and substantial superconducting volume fraction only happen in higher Sm-doping crystals with the nominal x 〉 0.10.The doping dependences of the c-axis length and onset Tc were summarized.The high-Tc observed in these quenched crystals may be attributed to simultaneous tuning of electron carriers doping and strain effect caused by lattice reduction of Sm-substitution.展开更多
文摘通过高温固相法合成了BaZr 1-x Sm x O 3-δ(x=0.05,0.1,0.15,0.2)电解质材料,并对材料的物相结构进行了XRD表征。分别在空气和4%H 2O/H 2中,温度范围为500~800℃下,通过电化学工作站测试了该电解质材料的电学性能。研究发现,稀土元素Sm的掺杂对BaZrO 3电解质材料的电学性能有重大影响,当Sm元素的掺杂量为0.15时,电解质的电导率达到最大值。结果表明,Sm的掺杂可以有效提高BaZrO 3电解质材料的电导率。
基金Project supported by National Natural Science Foundation of China(51371094,51471054)Young Teachers'Training Project,School of Materials and Metallurgy,Inner Mongolia University of Science and Technology(214CY012)
文摘Nanocrystalline and amorphous La_(2–x)Sm_xMg_(16)Ni+200wt.% Ni(x=0, 0.1, 0.2, 0.3, 0.4) alloys were prepared by mechanical milling technology. The structures of as-cast and milled alloys were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). Electrochemical performance of the alloy was studied by using an automatic galvanostatic system. The electrochemical impedance spectra(EIS) and Tafel polarization curves were measured by electrochemical workstation. The results indicated that the structures of the as-cast and milled alloys presented a multiphase structure with nanocrystalline and amorphous phase, moreover, transforming from nanocrystalline to amorphous phase with Sm doping. With the increase of Sm content, the maximum discharge capacity of the alloy was decreased from 922.6 to 649.1 m Ah/g, the high-rate discharge ability(HRD) was decreased, the cycle stability was strengthened, and the alloy exhibited excellent electrochemical kinetics. In addition, the charge-transfer resistance(R_(ct)) of alloy was lessened from 0.05874 to 0.02953 ? and the limiting current density(I_L) was descended from 2.08366 to 1.04592 A/g with increasing Sm content.
基金the the National Natural Science Foundation of China (50607013)China Talents Foundation of Ministry of Personnel of China (2007)
文摘The effect of Dy and Sm doping on microstructure and electric properties of bismuth titanate ceramics were investigated by means of XRD, SEM and AFM. The results showed that the grain growth habit was anisotropy of BIT ceramics doped with Dy, Sm at a concentration range of 0.5%~2.5%. However, c-axis decreased more obviously with increasing dopant concentration of Sm-doped sample than Dy-doped sample. As a result, the shape of grains of Sm-doped sample were granular, in contrast with Dy-doped sample with template particles. The grain size of Sm-doped sample decreased significantly, which led to a large dielectric constant and remanent polarization.
基金Project supported by the National Natural Science Foundation of China(Grant No.11474339)the National Basic Research Program of China(Grant Nos.2010CB923000 and 2011CBA00100)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB07020100)
文摘In this article,the Sm-doping single crystals Ca1-xSmxFe2As2(x = 0 0.2) were prepared by the Ca As flux method,and followed by a rapid quenching treatment after the high temperature growth.The samples were characterized by structural,resistive,and magnetic measurements.The successful Sm-substitution was revealed by the reduction of the lattice parameter c,due to the smaller ionic radius of Sm3+than Ca2+.Superconductivity was observed in all samples with onset Tc varying from 27 K to 44 K upon Sm-doping.The coexistence of a collapsed phase transition and the superconducting transition was found for the lower Sm-doping samples.Zero resistivity and substantial superconducting volume fraction only happen in higher Sm-doping crystals with the nominal x 〉 0.10.The doping dependences of the c-axis length and onset Tc were summarized.The high-Tc observed in these quenched crystals may be attributed to simultaneous tuning of electron carriers doping and strain effect caused by lattice reduction of Sm-substitution.