Evaluation of thermodynamic and kinetic stability of P-type transparent conducting oxide, SrCu2O2 under various oxygen partial pressures

Kinetic stability of transparent p-type conducting oxide, SrCu2O2, has been evaluated by using X-ray diffraction measurement and thermogravimetry. It was revealed that SrCu2O2 decomposed to mixture of CuO and Sr14Cu24O41 in air at temperatures above 300 °C. The decomposition reaction rate can be successfully explained by kinetic model assuming first-order chemical reaction. The rate constant can be suppressed with decreasing temperature and oxygen partial pressure. The activation energy for decomposition reaction of SrCu2O2 calculated from Arrhenius plot was 66 kJ/mol, which was lower than those of other transparent p-type semiconductors such as CuAlO2 and CuGaO2. The low decomposition temperature and activation energy for decomposition indicate that chemical stability of SrCu2O2 is far lower than those of other p-type conducting oxides.

▶ Thermodynamic and kinetic stabilities of SrCu2O2 under various P(O2) was estimated. ▶ The reaction rate for decomposition decreased with decreasing temperature and P(O2). ▶ The activation energy for decomposition of SrCu2O2 was estimated to be 66 kJ/mol. ▶ SrCu2O2 showed less stability than those of other transparent p-type semiconductors.