Effect of Pb Substitution on Superconducting and Normal State Electrical Properties of Bi2Sr2CaCu2O8+σ Nanopowders

2015 ◽  
Vol 827 ◽  
pp. 235-239
Author(s):  
Fahmi Astuti ◽  
Malik Anjelh Baqiya ◽  
Darminto

Abstract.The powders of Bi2-xPbxSr2CaCu2O8+δ(x=0; 0.4) superconductor have been prepared by using dissolved method followed by short period of sintering and calcination process . The purpose of this research is to study about the Pb doped effect to the properties of BSCCO nanopowders especially in the electric and superconducting properties. Based on the previous result, BSCCO nanopowders have ferromagnetic properties at the room temperature. This characteristic is not appeared in bulk superconductor. The 2212 phase of Bi-based system has been formed and observed by using X-ray diffraction (XRD) measurement. The superconducting quantum interference device (SQUID) observation showed that the Bi2-xPbxSr2CaCu2O8+δ(x=0; 0.4) samples exhibited diamagnetic behaviour at the critical temperature, Tc=76 K and 78 K. The sample with partial Pb substitution exhibited stronger permanency to the external magnetic field indicating presence of flux pinning. The four point probe (FPP) measurement showed that the sample partially doped with Pb has lower resistivity (more metallic) than the Pb-free sample in the normal state.

2007 ◽  
Vol 22 (5) ◽  
pp. 1396-1405 ◽  
Author(s):  
B. Seipel ◽  
R. Erni ◽  
Amita Gupta ◽  
C. Li ◽  
F.J. Owens ◽  
...  

The wurtzite polymorph of GaN was calcined with CuO in flowing nitrogen. As a result of this processing, both superconducting quantum interference device magnetometry and ferromagnetic resonance studies showed ferromagnetism in these samples at room temperature. These magnetic results are qualitatively consistent with very recent first-principle calculations [Wu et al., Appl. Phys. Lett.89, 062505 (2006)] that predict ferromagnetism in Cu-doped GaN. We focus in this paper on analyzing changes in the GaN atomic and electronic structure due to calcination with CuO using multiple analytical methods. Quantitative powder x-ray diffraction (XRD) showed changes in the lattice constants of the GaN due to the incorporation of copper (and possibly oxygen). Energy-dispersive x-ray spectroscopy proved the incorporation of copper into the GaN crystal structure. Electron-gun monochromated electron energy loss spectroscopy showed CuO calcinations-induced GaN band gap changes and indicated changes in the atomic arrangements due to the calcination process. The fine structure of the N K-edge showed differences in the peak ratios with respect to higher nominal CuO contents, corresponding to an increase in the c-lattice constant as confirmed by XRD.


2014 ◽  
Vol 934 ◽  
pp. 71-74
Author(s):  
Lian Mao Hang ◽  
Zhao Ji Zhang ◽  
Zhi Yong Zhang

Ni-doped rod-like ZnO particles with doping concentration of 1 at.% were synthesized at 200°C by hydrothermal method and characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and superconducting quantum interference device (SQUID). The results show that the as-synthesized samples are pure hexagonal wurtzite structure without metallic Ni or other secondary phases and display rod-like shape with smooth surface. The magnetization measurements reveal that the Ni-doped rod-like ZnO particles show ferromagnetic behavior at room temperature. The saturation magnetization and coercive field are 0.0046 emu/g and 15 Oe, respectively.


2012 ◽  
Vol 66 (3) ◽  
pp. 309-315 ◽  
Author(s):  
Tanja Barudzija ◽  
Alexey Gusev ◽  
Dragana Jugovic ◽  
Milena Marinovic-Cincovic ◽  
Miroslav Dramicanin ◽  
...  

Nanosized perovskite YTiO3 with the mean crystallite size of 18 nm was synthesized for the first time by mechanochemical treatment. The mechanochemical solid state reaction between commercial Y2O3 powder and mechanochemically synthesized TiO powder in molar ratio 0.5:1 was completed for 3 h in a high-energy planetary ball mill in argon atmosphere. The heating in vacuum at 1150 ?C for 12 h transforms nanosized YTiO3 to a well-crystallized single-phase perovskite YTiO3. Both samples were characterized by X-ray diffraction (XRD) and thermogravimetric (TGA/DTA) analyses, as well as superconducting quantum interference device magnetometer (SQUID) measurements.


2020 ◽  
Vol 855 ◽  
pp. 134-139
Author(s):  
Putu Eka Dharma Putra ◽  
Resky Irfanita ◽  
Bambang Triono ◽  
Malik Anjelh Baqiya ◽  
Darminto

The coexistence of ferromagnetism and paramagnetism of T’-Pr2-xCexCuO4+α-δ (T’-PCCO) nanoparticles with x = 0, and 0.10 have been studied intensively in the normal state. All samples were synthesized by a chemically dissolved method using HNO3 as a dissolving agent. The calcination process was performed at 1000°C for 15 h in air and followed by reduction annealing at 700°C in argon atmosphere for 10 h. All samples were first characterized by an x-ray diffraction (XRD) measureemnts followed by Rietveld and Maximum Entropy Method (MEM) analyseis. The result confirms the Ce-dependence and reduction annealing effect on the electron density at around the Cu site. The magnetic characterization was performed by using vibration sample magnetometer (VSM) indicating weak ferromagnetic properties at x = 0 and dominant paramagnetic properties at x = 0.10 at room temperature. Moreover, the weak ferromagnetic feature seems to remain after the annealing process. This signifies the coexist of weak ferromagnetism and paramagnetism at the normal state due to a number of oxygen vacancies in the crystal structure.


2020 ◽  
Vol 855 ◽  
pp. 154-159
Author(s):  
Fahmi Astuti ◽  
Vera Laviara Maghfirohtuzzoimah ◽  
Novita Sari ◽  
Deril Ristiani ◽  
Retno Asih ◽  
...  

Some studies of the usage of biomass to produce carbon-based compounds have been reported in the past. Here we report that palmyra sugar can be one of the sources to produce amorphous carbon (a-C) from biomass after the heating treatment at 250°C. In this paper, X-Ray Diffraction (XRD), Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX), Fourier Transform Infrared (FTIR) and Superconducting Quantum Interference Device (SQUID) measurements are reported in order to check the detailed properties of a-C from palmyra sugar. The XRD data at a diffraction peak position (2θ) of ~23o support the formation of a-C. The functional groups detected by FTIR spectra consist of C=C, C-C, C-O, C=O, C-H and O-H. The remnant magnetization (Mr), coercive field (Hc) and saturation magnetization are estimated as ~0.1 10-3 emu/g, ~50 Oe and ~9 10-3 emu/g, respectively. Soft ferromagnetism in a-C from palmyra sugar is confirmed, comparable with the magnetization result in the reduced graphene oxide (rGO) sample from coconut shell and rGO commercial material which have the same mixture hybridization. Some studies of the usage of biomass to produce carbon-based compounds have been reported in the past. Here we report that palmyra sugar can be one of the sources to produce amorphous carbon (a-C) from biomass after the heating treatment at 250°C. In this paper, X-Ray Diffraction (XRD), Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX), Fourier Transform Infrared (FTIR) and Superconducting Quantum Interference Device (SQUID) measurements are reported in order to check the detailed properties of a-C from palmyra sugar. The XRD data at a diffraction peak position (2θ) of ~23o support the formation of a-C. The functional groups detected by FTIR spectra consist of C=C, C-C, C-O, C=O, C-H and O-H. The remnant magnetization (Mr), coercive field (Hc) and saturation magnetization are estimated as ~0.1 10-3 emu/g, ~50 Oe and ~9 10-3 emu/g, respectively. Soft ferromagnetism in a-C from palmyra sugar is confirmed, comparable with the magnetization result in the reduced graphene oxide (rGO) sample from coconut shell and rGO commercial material which have the same mixture hybridization.


2010 ◽  
Vol 148-149 ◽  
pp. 1379-1382
Author(s):  
Hong Wang ◽  
Jian Chen ◽  
Rui Song Yang

The Magnetite (Fe3O4) nanoparticles have been successfully synthesized through a solvothermal route by using FeCl36H2O and NH4HCO3 as the starting materials. The as-prepared products are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), superconducting quantum interference device magnetometer (SQUID) and Brunauer-Emmett-Teller (BET). The uniform size of the Fe3O4 nanoparticles can be well controlled from 10 to 90 nm by changing the surfactants or the inorganic salts in the solvothermal process. The experiment results reveal that the magnetic properties of magnetite nanoparticles can be tuned by changing the particles size. In addition, the solvents in this reaction system have an important influence on the composition and morphology of the final products.


2012 ◽  
Vol 217-219 ◽  
pp. 142-145
Author(s):  
Hong Wang ◽  
Yong Zhong Jin ◽  
Tao Wang ◽  
Di Liu ◽  
Xue Fei Li

Ni/poly(m-toluidine)(PMT) nanocomposites were prepared by in situ chemical oxidative polymerization of m-toluidine (MT) monomer in the presence of Ni powder, with ammonium persulfate (APS) as oxidant and citric acid (C6H8O7) as dopant. The resultant products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and superconducting quantum interference device magnetometer (SQUID). The results exhibited that Ni/PMT nanocomposites show a ferromagnetic behavior with saturation magnetization strength (Ms) and coercivity of 28.4emu/g and 105.8Oe at room temperature. The prepared Ni/PMT composites were soft and ferromagnetic materials. Moreover, thermal Stability of nanocomposites was also investigated.


2009 ◽  
Vol 79-82 ◽  
pp. 635-638 ◽  
Author(s):  
Xin Wang ◽  
Hui Jia ◽  
Wei Tao Zheng ◽  
Wei Xu ◽  
Bei Hong Long

Fe-Co-N thin films with various Co content were synthesized on Si (111) substrate using facing-target magnetron sputtering by changing sputtering input power on Co target. During deposition, the input power on Fe target was kept at 160 W. The composition, structure, and magnetic properties were examined by X-ray photoelectron spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and superconducting quantum interference device. XRD and TEM investigations showed that at lower input power of 11.2 W on Co target, the phases in the film were -(Fe,Co)4N and Co3N. Increasing sputtering input power, the content of Co in the film increased. At input power of 14 W, film contained -(Fe,Co)8N phase was produced which exhibited higher saturation magnetization (252.85 Am2/kg) and lower value of coercivity (3.66 kAm-1), corresponded to the 12% content of Co in the film.


2020 ◽  
Vol 855 ◽  
pp. 58-63
Author(s):  
Malik Anjelh Baqiya ◽  
Putu Eka Dharma Putra ◽  
Resky Irfanita ◽  
Fitriana ◽  
Darminto ◽  
...  

Non-doped and strontium-doped lanthanum cuprates (La2CuO4 (LCO) and La1.85Sr0.15CuO4 (LSCO15)) in nano-sized particles were synthesized by the chemically dissolved technique employing HNO3 as the dissolving agent. The structural and magnetic properties were investigated by using an x-ray diffraction (XRD) apparatus and a superconducting quantum interference device (SQUID) magnetometer, respectively. The XRD patterns of LCO and LSCO15 show the formation of the single phase without impurities after the calcinations in air at 1100°C for 15 h and the post-annealing in oxygen at 800 °C for 24 h. The average crystallite sizes of LCO and LSCO15 samples were in a range of around 100 nm confirming nano-sized particles. The LCO and LSCO15 nanoparticles exhibit superconductivity at the superconducting (SC) transition temperature, Tc, of 23 K and 38 K, respectively. The magnetization curve measurements have revealed that both samples show the appearance of ferro- and dia-magnetic behavior at room temperature and the appearance of superconductivity at low temperatures. This result may indicate the coexistence of ferromagnetism and superconductivity below Tc in the nano-sized cuprates.


2012 ◽  
Vol 627 ◽  
pp. 638-641
Author(s):  
Hong Wang ◽  
Xue Fei Li ◽  
Chang Sheng Luo

Ni/poly(aniline-co-m-toluidine) nanocomposites were synthesized by in situ chemical oxidative polymerization of aniline with m-toluidine monomer in the presence of Ni powder, with ammonium persulfate (APS) as oxidant and citric acid (C6H8O7) as dopant. The structural, morphological and magnetic properties of these composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and superconducting quantum interference device magnetometer (SQUID). The results indicated that there is no chemical interaction between Ni powder and protonated copolymer, and Ni/poly(aniline-co-m-toluidine) nanocomposites displayed a ferromagnetic behavior with saturation magnetization strength and coercivity of 28.4emu/g and 105.8Oe at room temperature. The prepared composites were soft and ferromagnetic materials.


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