RETRACTED: Doping of Tin-oxides pinning centers into YBCO films by MOD method

Abstract

Abstract. Tin-oxides were doped into YBCO films as pinning centers to improve J C properties in a magnetic field. YBCO films were grown by a metal organic deposition process using trifluoroacetates starting solutions which contains tin compounds such as SnO 2 particles or tinacetylacetonate salts for pinning centers. J c of the YBCO films were enhanced by introducing pinning centers both SnO 2 and tin-acetylacetonates in the wide range of the magnetic angle. Especially, J C of YBCO film grown by the solution with tin-acetylacetnates increased in all magnetic field angles. XRD analysis and TEM observation revealed the existence of BaSnO 3 particles with the size of about 30 nm in the YBCO film grown by the solution with tinacetylacetnates. The BaSnO 3 nano particles were distributed randomly in the film and were considered to act as 3-dimentional pinning centers. IntroductionREBa 2 Cu 3 O 7-δ (REBCO, RE: rare earth elements) superconductors have been expected to use in many electric power applications since they have high critical current densities (J c ) at a liquid nitrogen temperature (77.3K) under self-field. A metal organic deposition (MOD) process using trifluoroacetates (TFA) is expected as a promising method for REBCO films since this technique can provide the films in a cost-effective process with non-vacuum system [1][2][3][4]. In order to apply REBCO for electric power applications, J c should be enhanced in a magnetic field (B). Recently, researches of J c enhancement for REBCO films have been proceeded by introducing artificial pinning centers into the films. It has been reported that J c properties in magnetic fields were well improved for REBCO films with pinning centers such as RE 2 O 3 and BaZrO 3 nano compounds or Ce-Gd-O nanowalls by the MOD process using TFA salts [5][6][7][8][9]. On the other hand, we have been reported that BaSnO 3 nano rods acted stronger than BaZrO 3 as pinning centers in REBCO film grown by a pulsed laser deposition method [10].In this paper, we grow YBCO films by a MOD process using TFA starting solutions. Tin compounds such as SnO 2 nano particles and soluble organic salts of tin were added into the TFA starting solutions as pinning centers. The effects of tin-compounds as pinning centers for YBCO films were discussed.

Structural and Superconducting Properties of Thermal Treatment-Synthesised Bulk YBa2Cu3O7−δ Superconductor: Effect of Addition of SnO2 Nanoparticles

“…These peaks were controversially indexed. While some groups assigned these peaks to BaSnO 2 [19,22], Choi et al indicate that these peaks belong to Y-Ba-Sn-O [18]. However, it can be concluded that Sn was not incorporated into the Y-123 crystal, and instead participated in the form of Sn-based secondary phases.…”

A comparative study on the flux pinning properties of Zr-doped YBCO film with those of Sn-doped one prepared by metal-organic deposition

“…On the other hand, many oxides, including RE 2 O 3 (RE: Y, Dy, and Ho) [19][20][21], perovskite BZO [22][23][24][25][26][27][28][29][30], BSO [31][32][33][34][35], BaHfO 3 [36], cubic-double-perovskite Ba 2 YTaO 6 [37] and YBa 2 SnO 5.5 [38], have also been incorporated into the YBCO and REBCO (RE: Sm, and Gd) matrix by the MOD process. Unlike nano-structured columnar defects in PLD-processed YBCO or REBCO films except RE 2 O 3 , all the above oxides formed point-like nanoparticles in MOD-processed YBCO films.…”