scholarly journals Importance of the pyrolysis for microstructure and superconducting properties of CSD-grown GdBa2Cu3O7−x-HfO2 nanocomposite films by the ex-situ approach

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Pablo Cayado ◽  
Hannes Rijckaert ◽  
Els Bruneel ◽  
Manuela Erbe ◽  
Jens Hänisch ◽  
...  
Keyword(s):  
Processing Parameters ◽  
Nanocomposite Films ◽  
Ex Situ ◽  
Superconducting Properties ◽  
Critical Temperatures ◽  
Solution Deposition ◽  
Nanoparticle Distribution ◽  
Current Densities ◽  
First Time ◽  
Lower Heating

Abstract For the first time, GdBa2Cu3O7−x nanocomposites were prepared by chemical solution deposition following the ex-situ approach. In particular, ~ 220 nm GdBa2Cu3O7−x-HfO2 (GdBCO-HfO2) nanocomposite films were fabricated starting from a colloidal solution of 5 mol% HfO2 nanoparticles. Hereby, one of the main challenges is to avoid the accumulation of the nanoparticles at the substrate interface during the pyrolysis, which would later prevent the epitaxial nucleation of the GdBCO grains. Therefore, the effect of pyrolysis processing parameters such as heating ramp and temperature on the homogeneity of the nanoparticle distribution has been investigated. By increasing the heating ramp to 300 °C/h and decreasing the final temperature to 300 °C, a more homogenous nanoparticle distribution was achieved. This translates into improved superconducting properties of the grown films reaching critical temperatures (Tc) of 94.5 K and self-field critical current densities ($${J}_{\mathrm{c}}^{\mathrm{sf}}$$ J c sf ) at 77 K of 2.1 MA/cm2 with respect to films pyrolyzed at higher temperatures or lower heating ramps.

scholarly journals Rapid Pyrolysis of SmBa2Cu3O7-δ Films in CSD-MOD Using Extremely-Low-Fluorine Solutions

Coatings ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 31 ◽  
Author(s):  
Minjuan Li ◽  
Pablo Cayado ◽  
Manuela Erbe ◽  
Alexandra Jung ◽  
Jens Hänisch ◽  
...  
Keyword(s):  
Crystallization Temperature ◽  
Chemical Solution Deposition ◽  
Growth Process ◽  
Chemical Solution ◽  
Superconducting Properties ◽  
Heating Rates ◽  
Critical Temperatures ◽  
Solution Deposition ◽  
Rapid Pyrolysis

SmBa2Cu3O7-δ (SmBCO) films have been prepared by chemical solution deposition starting from extremely-low-fluorine solutions (7% fluorine with respect to standard full trifluoroacetate solutions). Smooth and homogeneous SmBCO films could be achieved at heating rates of up to 20 °C/min during pyrolysis. The best films were achieved at a crystallization temperature of 810 °C and 50 ppm of oxygen partial pressure. At these conditions, the ~270 nm thick SmBCO films grow mostly c-axis-oriented with J c sf values at 77 K of ~2 MA/cm2 and critical temperatures Tc of up to 95.0 K. These results demonstrate that using extremely-low-fluorine solutions is very attractive since the production rate can be largely increased due to the solutions’ robustness during pyrolysis retaining a remarkable quality of the grown films. Nevertheless, further optimization of the growth process is needed to improve the superconducting properties of the films.

scholarly journals CSD-Grown Y1−xGdxBa2Cu3O7−δ-BaHfO3 Nanocomposite Films on Ni5W and IBAD Technical Substrates

Nanomaterials ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 21 ◽  
Author(s):  
Pablo Cayado ◽  
Hannes Rijckaert ◽  
Manuela Erbe ◽  
Marco Langer ◽  
Alexandra Jung ◽  
...  
Keyword(s):  
Chemical Solution Deposition ◽  
Growth Process ◽  
Growth Conditions ◽  
Coated Conductors ◽  
Nanocomposite Films ◽  
Chemical Solution ◽  
Superconducting Properties ◽  
High Quality ◽  
Solution Deposition ◽  
Structure Morphology

Chemical solution deposition (CSD) was used to grow Y1−xGdxBa2Cu3O7−δ-BaHfO3 (YGBCO-BHO) nanocomposite films containing 12 mol% BHO nanoparticles and various amounts of Gd, x, on two kinds of buffered metallic tapes: Ni5W and IBAD. The influence of the rare-earth stoichiometry on structure, morphology and superconducting properties of these films was studied. The growth process was carefully studied in order to find the most appropriate growth conditions for each composition and substrate. This led to a clear improvement in film quality, probably due to the reduction of BaCeO3 formation. In general, the superconducting properties of the films on Ni5W are significantly better. For x > 0.5, epitaxial ~270 nm thick YGBCO-BHO films with Tc > 93 K and self-field Jc at 77 K ~2 MA/cm² were obtained on Ni5W. These results highlight the potential of this approach for the fabrication of high-quality coated conductors.

Lanthanum zirconate: A single buffer layer processed by solution deposition for coated conductor fabrication

2002 ◽  
Vol 17 (9) ◽  
pp. 2181-2184 ◽  
Author(s):  
S. Sathyamurthy ◽  
M. Paranthaman ◽  
H-Y. Zhai ◽  
H. M. Christen ◽  
P. P. Martin ◽  
...  
Keyword(s):  
Buffer Layer ◽  
Low Cost ◽  
Sol Gel ◽  
Single Layer ◽  
Coated Conductors ◽  
Buffer Layers ◽  
Solution Deposition ◽  
Sol Gel Process ◽  
Current Densities ◽  
First Time

A single layer of La2Zr2O7 (LZO), deposited on textured Ni and Ni–1.7% Fe–3% W (Ni–W) tapes by a low-cost sol-gel process, is used as buffer layer for the growth of YBa2Cu3O7−δ (YBCO) coated conductors. It is shown for the first time that such single buffer layers can be used for the deposition of YBCO yielding critical current densities (Jc) that are comparable to those typically obtained using CeO2/YSZ/Y2O2 trilayers on identical substrates, i.e., in excess of 1 MA/cm2 at 77 K and self-field. The properties of the YBCO films and the dependence of Jc on thickness of the LZO layer are investigated.

Structural and superconducting properties of Nb3Sn film for superconducting radio-frequency cavities synthesized via bronze route

2021 ◽  
pp. 2151030
Author(s):  
Feng Pan ◽  
Ming Lu ◽  
Andong Wu ◽  
Qingwei Chu ◽  
Ziwei Lu ◽  
...  
Keyword(s):  
Thin Film ◽  
Radio Frequency ◽  
Ex Situ ◽  
Tubular Furnace ◽  
Superconducting Properties ◽  
X Ray Diffraction ◽  
Critical Temperatures ◽  
X Ray ◽  
Superconducting Radio Frequency ◽  
A New Technique

Superconducting Nb3Sn films were synthesized via the ex-situ annealing of Nb-coated bronze precursors. The precursors were prepared by sputtering 2 [Formula: see text]m of niobium film onto a bronze surface. The annealing was conducted in a vacuum tubular furnace at a temperature not higher than 700[Formula: see text]C. By changing the annealing time and temperature, a series of Nb3Sn samples with critical temperatures ([Formula: see text] > 16 K were obtained. X-ray diffraction confirmed the existence of the cubic Nb3Sn phase (A15 structure), whereas magnetic moment measurements indicated that critical temperature of the studied samples ranged from 16.2 to 16.5 K. Therefore, this study explores a new technique appropriate for creating copper-based Nb3Sn thin-film-coated superconducting radio-frequency (TFSRF) cavities.

MgB2 Composite Superconductors Made by Ex Situ and In Situ Process

2006 ◽  
Vol 47 ◽  
pp. 131-136 ◽  
Author(s):  
Pavol Kováč ◽  
I. Hušek ◽  
T. Melišek
Keyword(s):  
Current Density ◽  
Transport Current ◽  
Ex Situ ◽  
Boron Diffusion ◽  
Critical Temperatures ◽  
Mgb2 Wires ◽  
Composite Superconductors ◽  
Current Densities ◽  
Composite Wires

Generally, two basic routes called as in-situ and ex-situ process are used for composite MgB2 wires now. Mentioned processes have been used for making of single-core composite wires. The applied heat treatment parameters influence the microstructure of MgB2 phase, critical temperature and critical current density, but it has also decisive effect on the MgB2/metal reaction. It was found that the transport current densities are much more sensitive to the used sheath material than critical temperatures. The main factors limiting the transport current density are cracks introduced by deformation and porosity caused by the boron diffusion in ex-situ and in-situ wires, respectively.

Fabrication of large grain YBCO by seeded peritectic solidification

1996 ◽  
Vol 11 (4) ◽  
pp. 786-794 ◽  
Author(s):  
Wai Lo ◽  
D. A. Cardwell ◽  
C. D. Dewhurst ◽  
S-L. Dung
Keyword(s):  
Growth Process ◽  
Melting Process ◽  
Processing Parameters ◽  
Vibrating Sample Magnetometry ◽  
Superconducting Properties ◽  
Solidification Kinetics ◽  
Peritectic Melting ◽  
Superconducting Ceramics ◽  
Peritectic Solidification ◽  
Current Densities

The ability to process large grain, uniform high temperature superconducting ceramics that exhibit high critical current densities at 77 K is essential if the enormous potential of these materials for a range of permanent magnet-type applications is to be realized. We report a study of the fabrication of large grain YBa2Cu3O7−δ by seeded peritectic solidification in which key processing parameters such as the peritectic melting process, the seed-YBCO reaction, and the YBCO solidification kinetics are investigated in detail. Evolution of the sample microstructure during various stages of the growth process, in particular, has been studied extensively. The superconducting properties of specimens cut from different regions of large grain samples have been measured using vibrating sample magnetometry, and the results correlated with the microstructure of the materials.

Enhanced electrical conductivity of Au–LaNiO3 nanocomposite thin films by chemical solution deposition

RSC Advances ◽  
2015 ◽  
Vol 5 (94) ◽  
pp. 76783-76787 ◽  
Author(s):  
H. L. Wang ◽  
X. K. Ning ◽  
Z. J. Wang
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Electrical Properties ◽  
Chemical Solution Deposition ◽  
Nanocomposite Films ◽  
Chemical Solution ◽  
Solution Deposition ◽  
Nanocomposite Thin Films ◽  
One Step

Au–LaNiO3 (Au–LNO) nanocomposite films with 3.84 at% Au were firstly fabricated by one-step chemical solution deposition (CSD), and their electrical properties were investigated.

Chemical Solution Deposition of Lanthanum Zirconate Buffer Layers on Biaxially Textured Ni–1.7% Fe–3% W Alloy Substrates for Coated-conductor Fabrication

2002 ◽  
Vol 17 (6) ◽  
pp. 1543-1549 ◽  
Author(s):  
S. Sathyamurthy ◽  
M. Paranthaman ◽  
T. Aytug ◽  
B. W. Kang ◽  
P. M. Martin ◽  
...  
Keyword(s):  
Sol Gel ◽  
Rf Sputtering ◽  
Cube Texture ◽  
Dip Coating ◽  
Buffer Layers ◽  
Lanthanum Zirconate ◽  
Solution Deposition ◽  
Ybco Films ◽  
Current Densities ◽  
Gel Processing

Sol-gel processing of La2Zr2O7 (LZO) buffer layers on biaxially textured Ni–1.7% Fe–3% W alloy substrates using a continuous reel-to-reel dip-coating unit has been studied. The epitaxial LZO films obtained have a strong cube texture and uniform microstructure. The effects of increasing the annealing speed on the texture, microstructure, and carbon content retained in the film were studied. On top of the LZO films, epitaxial layers of yttria-stabilized zirconia and Ceria (CeO2) were deposited using rf sputtering, and YBa2Cu3Ox (YBCO) films were then deposited using pulsed laser deposition. Critical current densities (Jc) of 1.9 MA/cm2 at 77 K and self-field and 0.34 MA/cm2at 77 K and 0.5 T have been obtained on these films. These values are comparable to those obtained on YBCO films deposited on all-vacuum deposited buffer layers and the highest ever obtained using solution seed layers.

Preparation and Growth of Pb2Sr2Y0.5Ca0.5Cu3O8+δ Thin Film Superconductors

1992 ◽  
Vol 285 ◽  
Author(s):  
S.H.H. Naqvi ◽  
M. Vickers ◽  
S. Tarling ◽  
P. Barnes ◽  
I.W. Boyd
Keyword(s):  
Thin Film ◽  
Pulsed Laser ◽  
Growth Conditions ◽  
Laser Deposition ◽  
Ex Situ ◽  
Dc Resistivity ◽  
Basic Set ◽  
Zero Resistance ◽  
Van Der Pauw ◽  
First Time

ABSTRACTThe lead based superconductor Pb2Sr2Y0.5Ca0.5Cu3O8+δ is a most complex material. If any oxygen is present in the PbO-CuOδ-PbO sandwich layer (i.e. if δ>0) the superconductivity deteriorates. This is also a most difficult material to grow not only because of the large number of cation stoichiometries which have to be precisely balanced but also because of the tendency for multiple phases to form. Pulsed laser deposition (PLD) has been applied to prepare thin films of the 2213-phase on MgO (100) single crystal substrates at low temperature (300°C) in low oxidizing atmospheres. A basic set of ex-situ growth conditions has been determined which produce for the first time good quality films of this material as characterized by DC resistivity using the Van der Pauw method, as well as EDX and XRD. The layers are reasonably c-axis oriented and display a superconducting onset transition temperature of 79K and zero resistance at 65K after subsequent annealing in a nitrogen ambient.

SUPERCONDUCTING PROPERTIES OF BSCCO (2223) ULTRATHIN FILMS

2002 ◽  
Vol 09 (05n06) ◽  
pp. 1757-1760
Author(s):  
L. NAVARRETE ◽  
A. MARIÑO ◽  
H. SÁNCHEZ
Keyword(s):  
Electrical Properties ◽  
Magnetron Sputtering ◽  
Structural Characterization ◽  
Ultrathin Films ◽  
Rf Magnetron Sputtering ◽  
Ex Situ ◽  
Thermal Treatments ◽  
Superconducting Properties

Ultrathin films of (Bi–Pb)–Sr–Ca–Cu–O (2223) were produced by ex situ RF magnetron sputtering on MgO (100) substrates. Films with different thermal treatments and thickness varying between 30 nm and 300 nm were obtained and studied systematically. A structural characterization of these samples was carried out and correlated with their electrical properties and thickness.

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