Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Low temperature heat capacity of bulk and nanophase ZnO and Zn1-xCoxO wurtzite phases

ma, C.[Chengcheng], Shi, Q.[Quan], Woodfield, B. F.[Brian F.], Navrotsky, A.[Alexandra]
J. Chem. Thermodyn. 2013, 60, 191-196
ABSTRACT
The low temperature heat capacity of the ZnO CoO solid solution system was measured from 2 to 300 K using the heat capacity option of a Quantum Design Physical Property Measurement System (PPMS). The thermodynamic functions in this temperature range were derived by curve fitting. The standard entropies of bulk ZnO and bulk ZnO CoO (wurtzite, 18 mol% CoO) at T = 298.15 K were calculated to be (43.1 +- 0.4) J mol 1 K 1 and (45.2 +- 0.5) J mol 1 K 1, respectively. The surface entropy of ZnO was evaluated to be (0.02 +- 0.01) mJ K 1 m 2, which is essentially zero. No sharp magnetic transitions were observed in the solid solution samples. The nanophase solid solution, 12 mol% CoO, appears to bind H2O on its surface more strongly than ZnO.
Compounds
# Formula Name
1 OZn zinc(II) oxide
2 CoO cobalt oxide
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Thin-film microcalorimeter
  • 59
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Thin-film microcalorimeter
  • 58
  • POMD
  • 1
  • Molar enthalpy, kJ/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Thin-film microcalorimeter
  • 58
  • POMD
  • 1
  • Molar entropy, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Thin-film microcalorimeter
  • 58
  • POMD
  • 2
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Mole fraction - 2; Crystal
  • Crystal
  • Thin-film microcalorimeter
  • 140
  • POMD
  • 2
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Mole fraction - 2; Crystal
  • Crystal
  • Thin-film microcalorimeter
  • 58