Advertisement

Nonstoichiometric Phases—Composition, Properties and Phase Transitions

  • David SedmidubskýEmail author
  • Pavel Holba
Chapter
Part of the Hot Topics in Thermal Analysis and Calorimetry book series (HTTC, volume 11)

Abstract

Nonstoichiometric phases constitute a large family of technologically important materials. Among them, the inorganic materials whose variable stoichiometry of some components originates from their exchange with surrounding atmosphere represent particular thermodynamic systems referred to a partly open system. The phase equilibria in these systems including the homogeneous crystallochemical reactions of the involved crystal defects can be effectively treated using the thermodynamic potential called hyper-free energy derived from the Gibbs free energy by Legendre transformation with respect to the amounts of free components. In this chapter, we focus on general thermodynamic description of systems with variable content of components shared with a dynamical atmosphere, their essential material quantities being influenced by variable stoichiometry, conditions for homogeneous crystallochemical equilibria as well as for phase transitions. The influence of variable stoichiometry on material properties such as isobaric thermal expansion, isothermal compressibility and in particular heat capacity is analyzed and divided into two parts: the direct effect on conventional isoplethal quantities due to deviation from stoichiometry, and so-called saturation contributions determining the difference in material properties measured under isoplethal and isodynamical conditions (constant activities of free components). In the last part, the construction of phase diagrams of partly open systems is demonstrated on several examples of oxide systems, and the relevant phase transitions are classified and discussed.

Keywords

Stable Component Clapeyron Equation Isochoric Heat Capacity Dynamical Atmosphere Free Component 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

P. Holba acknowledges the support of Ministry of Education of the Czech Republic in the framework of CENTEM PLUS project (LO1402) operated under the “National Sustainability Programme I.”

References

  1. 1.
    Hoitsema C (1895) Palladium und Wasserstoff. Z Phys Chem 17:1–42Google Scholar
  2. 2.
    Wald F (1897) Elementare chemische Betrachtungen. Z Phys Chem 24:633–650Google Scholar
  3. 3.
    Wald F (1899) Was ist ein chemisches Individuum. Z Phys Chem 28:13–16Google Scholar
  4. 4.
    Holba P (2015) Termodynamický popis tepelných kapacit v nestechiometrických fázích (In Czech). Chemické Listy 109:113–116Google Scholar
  5. 5.
    Šesták J, Holba P, Gavrichev K (2014) Reinstatement of thermal analysis tradition in Russia and related East European interactions. J Therm Anal Cal 119:779–784Google Scholar
  6. 6.
    Kurnakov NS (1914) Compound and chemical individuum. Bull Acad Imp Sci de St Pétersbourhg 321–328Google Scholar
  7. 7.
    Chaudron G (1921) Reversible reactions of hydrogen and carbon monoxide on metallic oxides. Ann Chem 16:221–281Google Scholar
  8. 8.
    Schenck R, Dingmann T (1927) Gleichgewichtsuntersuchungen bei der Reduktions, Oxydations und Kohlungsvorgänge beim Eisen III. Z Anorg Chem 166:113–154CrossRefGoogle Scholar
  9. 9.
    Schottky W, Wagner C (1930) Theorie der geordneten Mischphasen. Z Phys Chem (Leipzig) B 11:163–220Google Scholar
  10. 10.
    Darken LS, Gurry RW (1945) The system iron–oxygen. I. The Wüstite field and related equilibria. J Am Chem Soc 67:1398–1412CrossRefGoogle Scholar
  11. 11.
    Darken LS, Gurry RW (1946) The system iron–oxygen. II. Equilibrium and thermodynamics of liquid oxide and other phases. J Am Chem Soc 68:798–816CrossRefGoogle Scholar
  12. 12.
    Aricò AS, Bruce P, Scrosati B, Tarascon J-M, Van Schalkwijk W (2005) Nanostructured materials for advanced energy conversion and storage devices. Nat Mater 4:366–377CrossRefGoogle Scholar
  13. 13.
    O’regan B, Grätze M (1991) A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films. Nature 353:737–740CrossRefGoogle Scholar
  14. 14.
    Ohta H, Hosono H (2004) Transparent oxide optoelectronics. Mater Today 7(6):42–51CrossRefGoogle Scholar
  15. 15.
    Keller F, Hunter M, Robinson D (1953) Structural features of oxide coatings on aluminum. J Electrochem Soc 100:411–419CrossRefGoogle Scholar
  16. 16.
    Weckhuysen BM, Keller DE (2003) Chemistry, spectroscopy and the role of supported vanadium oxides in heterogeneous catalysis. Catal Today 78:25–46CrossRefGoogle Scholar
  17. 17.
    Holba P (1992) Thermodynamics of partially open systems. Czech J Phys B 42:549–575CrossRefGoogle Scholar
  18. 18.
    Sedmidubský D, Strejc A, Nevřiva M, Leitner J, Martin C (2003) Structural and phase relations in the Sr–Mn–O system. Solid State Phenom 90–91:427–432CrossRefGoogle Scholar
  19. 19.
    Holba P, Sedmidubský D (2013) Heat capacity equations for nonstoichiometric solids. J Therm Anal Calorim 113:239–245CrossRefGoogle Scholar
  20. 20.
    Sedmidubský D, Holba P (2015) Material properties of nonstoichiometric solids. J Therm Anal Calorim 1120:183–188CrossRefGoogle Scholar
  21. 21.
    Holba P, Sedmidubský D (2013) Crystal defects and nonstoichiometry contributions to heat capacity of solids, Chapter 3 in book: thermal analysis of micro- nano- and non-crystalline materials: transformation, crystallization, kinetics and thermodynamics. In: Šesták J, Šimon P (eds) Springer, pp 53–74Google Scholar
  22. 22.
    Jankovský O, Sedmidubský D, Sofer Z, Rubešová K, Růžička K, Svoboda P (2014) Oxygen non-stoichiometry and thermodynamic properties of Bi2Sr2CoO6+δ ceramics. J Eur Ceram Soc 34:1219–1225CrossRefGoogle Scholar
  23. 23.
    Sedmidubský D, Leitner J, Knížek K, Strejc A, Veverka M (2000) Phase equilibria in Hg–Ba–Cu–O systém. Phys C 329:191–197CrossRefGoogle Scholar
  24. 24.
    Voňka P, Leitner J, Sedmidubský D (2008) Topology of potential phase diagrams of partially open condensed systems. Collect Czech Chem Commun 73(3):372–387CrossRefGoogle Scholar
  25. 25.
    Sedmidubský D, Jakeš V, Jankovský O, Leitner J, Sofer Z, Hejtmánek J (2012) Phase equilibria in Ca–Co–O system. J Sol St Chem 194:199–205CrossRefGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2017

Authors and Affiliations

  1. 1.Department of Inorganic ChemistryUniversity of Chemistry and Technology PraguePraha 6Czech Republic
  2. 2.New Technologies Research CentreUniversity of West BohemiaPragueCzech Republic

Personalised recommendations