The nucleation and growth mechanism of the electrodeposition of Tl2Ba2Ca2Cu3O10superconducting thin films on Al-substrate

The present study demonstrates the nucleation and growth mechanism of the Tl2Ba2Ca2Cu3O10 (Tl-2223) superconductor by the electrodeposition technique on low cost aluminum coated glass (ALCG)-substrate at low processing temperature and short synthesis time, which is one of the most important aspects demanded of superconducting materials in practical applications. Superconducting thin films of Tl-2223 have been fabricated by the electrodeposition process on crystalline ALCG-substrate for the first time. The electrodeposition potential was optimized by studying the electrochemical behavior of the precursors by cyclic voltammetry (CV). All the precursor components, including Tl, were deposited at an optimized potential of −3 V with respect to a saturated calomel electrode (SCE) for 5 min followed by the heat treatment at 700 °C for 2 h in flowing oxygen atmosphere. X-ray diffraction (XRD) studies confirmed the presence of the Tl-2223 phase with marked preferential orientation along the c-axis. Atomic force microscopy (AFM) images show uniform and compact morphology with growth of rod-like grains (50–100 nm width) of Tl-2223 along the plane parallel to the ALCG-substrate. The transport measurement for Tl-2223 film showed a superconducting transition temperature Tc of 125 K and a critical current Jc of 0.31 × 106 A cm−2 at 77 K.