Nanocrystalline YBa 2Cu 3O 7−δ/Ag composite particles produced by aerosol decomposition

Abstract

YBa 2Cu 3O 7−δ (1-2-3) powders containing silver have been prepared by aerosol decomposition for the first time. The primary phase observed by X-ray diffractometry and transmission electron microscopy (TEM) is 1-2-3. Metallic Ag grains have also been identified by using energy-dispersive spectroscopy and diffraction pattern analysis in the TEM. For reactor operating temperatures of 1000° C, each YBa 2Cu 3O 7−δ particle has associated with it a single Ag grain which does not wet the superconductor. Thus, the Ag is contained in discrete grains dispersed uniformly throughout the powder. Both materials are nanocrystalline with a grain size on the order of 10 to 80 nm.