  We report a detailed study performed on La2Zr2O7 (LZO) pyrochlore material
grown by Metal-Organic Decomposition (MOD) method as buffer layers for
YBa2Cu3O7-x (YBCO) coated conductors. High quality epitaxial LZO thin films
have been obtained on single crystal (SC) and Ni-5%at.W substrates. In order to
evaluate structural and morphological properties, films have been characterized
by means of X-ray diffraction analyses (XRD), atomic force microscope (AFM) and
scanning electron microscope (SEM). Precursors solutions and heat treatments
have been studied by thermogravimetric analyses (TG-DTA-DTG) and infrared
spectra (FT-IR) with the aim of optimizing the annealing process. Thin films of
YBCO have been deposited by pulsed laser ablation (PLD) on this buffer layers.
The best results obtained on SC showed YBCO films with critical temperature
values above 90 K, high self field critical current density values (Jc > 1
MA/cm2) and high irreversibility field values (8.3 T) at 77 K together with a
rather high depinning frequency vp (0.5 T, 77 K)>44 GHz as determined at
microwaves. The best results on Ni-5%at.W has been obtained introducing in the
heat treatment a pyrolysis process at low temperature in air in order to remove
the residual organic part of the precursor solution.
