LaCoO3 nanosystems by a hybrid CVD/sol-gel approach

J Nanosci Nanotechnol. 2005 May;5(5):781-5. doi: 10.1166/jnn.2005.099.

Abstract

LaCoO3 nanosystems are receiving increasing attention for the development of innovative fuel cells and heterogeneous catalysts. In this report, we describe the synthesis of nanophasic LaCoO3 thin films by a hybrid chemical vapor deposition (CVD)/sol-gel (SG) approach. The adopted strategy consists in the CVD of La-O-based systems on SG cobalt oxide xerogels CoOx(OH)y at temperatures as low as 200 degrees C and in the subsequent thermal treatment in air (400-800 degrees C, 2-8 h). In this context, particular attention is devoted to achieving an intimate La/Co intermixing already in the as-prepared systems, in order to favor reactions yielding a single La-Co-O phase with uniform composition. The obtained results point out to the formation of pure and structurally homogeneous LaCoO3 nanosystems after annealing at 700 degrees C, 2 h, with a typical grain-like morphology. More severe thermal treatment resulted in the thermal decomposition of LaCoO3 nanocrystallites.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cobalt / analysis
  • Cobalt / chemistry*
  • Crystallization / methods*
  • Lanthanum / analysis
  • Lanthanum / chemistry*
  • Materials Testing
  • Molecular Conformation
  • Nanostructures / analysis
  • Nanostructures / chemistry*
  • Nanostructures / ultrastructure*
  • Nanotechnology / methods*
  • Oxides / analysis
  • Oxides / chemistry*
  • Phase Transition
  • Semiconductors
  • Volatilization

Substances

  • Oxides
  • Cobalt
  • Lanthanum
  • cobalt oxide