Heat capacity on data of DSC calorimetry and thermodynamic functions of barium cerate doped by holmium and indium oxides in the temperature range of 200–700 K

For the first time the heat capacity of BaCe 0.7 Ho 0.2 In 0.1 O 2.85 was measured in the temperature range of 200–700 K. Calorimetric experiments were performed using differential scanning calorimetry (DSC). We identified three areas where heat capacity was smoothly varying: 200–500, 500–573, and 573–700 K. The heat capacity in all these areas has been described by polynomials. Heat capacity of BaCe 0.7 In 0.1 Ho 0.2 O 2.85 in the temperature range 200–500 K is well described by a polynomial: C p,m ° = 55.606 + 0.23556 T − 1.9546 × 10 −4 T 2 − 1.2072 × 10 −8 T 3 . The heat capacity in the range of 500–573 K is well described by a polynomial of the form: C p,m ° = 429.55 − 0.66985 T + 4.0801 × 10 −4 T 2 − 1.8387 × 10 7 /T 2 . The heat capacity in the temperature range 573–700 K is well described by the equation: C p,m ° = 135.72 − 0.060195 T + 6.7994 × 10 −5 T 2 . The enthalpy increments ( H m ° ( T ) − H m ° (298.15)) and entropy ( S m ° ( T )) were evaluated from heat capacity data ( T = 200–700 K).