Modelling Hydrothermal Synthesis of Ceramic Composite Nanomaterials

Robert R. Piticescu 

Institute for Non-ferrous and Rare Metals, 102 Biruintei Blvd., Pantelimon 73957, Romania


Modelling hydrothermal synthesis of ceramic composite NANOmaterials

R.R. Piticescu*, Roxana M. Piticescu*, A. Motoc* and D. Taloi**

*Institute for Non-ferrous and Rare Metals, 102 Biruintei Blvd., 73957
Pantelimon-Bucharest, Romania
** University POLITEHNICA Bucharest, 313 Splaiul Independentei,
Bucharest, Romania
Contact person : E-mail:

Hydrothermal procedures are interesting chemical routes
for synthesis of many important ceramic nanostructured materials.
Processes include hydrothermal reaction synthesis from solutions and
hydrothermal treatment of amorphous hydrous oxides. Nanostructured
materials can be obtained controlling nucleation by
solubilisation-reprecipitation mechanisms and particle growth.
Thermodynamic prediction of equilibrium compounds formed in the
process is difficult; a reliable estimation may be done using the
Pourbaix diagrams. Some important advantageous of these procedures
are: direct producing of crystalline materials at low synthesis
temperatures in one step, versatility, utilization of low cost
inorganic precursors and important reduction of pollutant effluents,
in accordance with the new environmental protection regulations.
Fundamental studies regarding the mechanisms and kinetics
of the synthesis processes were developed. Considering that in the
initial stage at low pH the nucleation takes place by the hydrolysis
reactions Mz+ +z H[2]O Ű M(OH)[z] + zH+ and knowing the initial molar
concentration of the metal in solution S[0] = [Mz+], putting the
equilibrium concentration of the precipitated species P[e] =
=[M(OH)[z]][e] and noting that according to reaction stoichiometry
[H+]z[e] = (1/z) P[e], one may calculate the equilibrium concentration
of precipitated complex from solution solving the polynomial
(1/z)z (P[e])z+1 + K[h,g] P[e] - K[h,g] S[0]=0
We approximated the nuclei radius from
r[0] ť (3 k[B] /4pr[0])1/3 (P[e])1/3 (-lnK[h,g])-1/3
where k[B] is the Boltzmann constant.
Hydrothermal synthesis of nanopowders of yttria-doped
zirconia, zirconia-alumina nanocomposites, lead zirconate titanate or
barium titantate were successfully done starting form inorganic
soluble precursors.
Thin films of yttria doped zirconia ceramics or PZT could also be
deposited from solutions precursors and suspensions under hydrothermal
using our hydrothermal/electrochemical system composed from CORTEST 2L
Teflon autoclave/VOLTALAB galvanostat/potentiostat. Ni or Ti foils are
the working electrode, the counter-electrode being platinated Nb and
an external AgCl reference electrode with a saline junction was used.


Related papers
  1. Novel synthesis methods of Co-doped ZnO Nanopowders
  2. Synthesis of doped ZnO nanopowders in microwave hydrothermal reactors
  3. Synthesis of Al doped ZnO nanopowders and their enhanced luminescence
  4. High pressure-low temperature synthesis of new nanostructured compounds  
  5. Combining microwave and pressure techniques for hydrothermal synthesis of ZnO and ZrO2 nanopowders doped with a range of metal ions
  6. Luminescence properties of zinc oxide nanopowders doped with Al ions obtained by the hydrothermal and vapour condensation methods.
  7. Microstructural analysis of ZnO powders with different concentrations of Al dopant obtained by means of hydrothermal synthesis
  8. Mapping dopants effects in the High pressure synthesis of nanostructured zinc oxide
  9. High pressure-low temperature synthesis of new nanostructured compounds
  10. Zirconia-based nanomaterials for oxygen sensor - generation, characterisation and optical properties
  11. Cathodoluminescence of Al doped ZnO nanopowders
  12. Morphology of Al doped Zinc Oxide Obtained using Hydrothermal and Vapour Condensation Methods
  13. Hydrothermal synthesis of doped oxide nanomaterials: a review
  14. Morphology of Al doped zinc oxide obtained by the vapour condensation method
  15. Morphology of Al-Doped Zinc Oxide Obtained by the Vapour Condensation Methods
  16. Hydrothermal synthesis: opportunities for technology transfer in advanced materials
  17. New routes for the synthesis of Al-doped ZnO transparent nanomaterials
  18. Synthesis of Al-doped ZnO nanomaterials with controlled luminescence properties
  19. Hydrothermal synthesis of nanomaterials: bringing materials closer to life
  21. Zirconia pressure sensors: from nanopowders to device

Presentation: oral at High Pressure School 1999 (3rd), by CE System
See On-line Journal of High Pressure School 1999 (3rd)

Presentation: oral at E-MRS Fall Meeting 2002, by Robert R. Piticescu
See On-line Journal of E-MRS Fall Meeting 2002

Submitted: 2003-02-16 17:33
Revised:   2009-06-08 12:55