Electrodeposition of biaxially aligned Tl-based superconductors on Ag tapes

An alternative preparation method of T1(1212) and T1(1223) biaxially aligne d tapes on Ag was developed: electrodeposition. This method is based on the co-deposition of the metals by an electrochemic al process followed by a high temperature heat treatment in order to form t he superconducting phase. Nitrates of the metals are dissolved in DMSO and the deposition on conducting substrates is performed in a standard three el ectrodes cell. The thermal treatment is performed in a high isostatic press ure furnace (1 bar O-2/ 50 bar He) in order to prevent TI evaporation. The main advantage of this low cost technique is that it is very fast, (sim ilar to1 mum/min) and can be easily scaled up to produce long length tapes in a continuos process. The desired stoichiometry is obtained by varying it eratively the concentration of nitrates in the starting solution. Moreover, the reaction temperature and time of the thermal treatment are drastically reduced with respect to the powder synthesis due to the amorphous form of the precursor. Excellent biaxial alignment is observed on both {110} Ag single crystal and textured Ag tapes, while epitaxial growth is observed on SrTiO3 single cry stal. T-c of 118 K and 60 K were measured resistively for T1(1223) and T1(1 212) samples, respectively.