Synthesis and electrical conductivity of Y1−xMn1−yO3−δ

YMnO3-related materials [stoichiometric (Y/Mn =1), and Y or Mn deficient] were synthesized by a traditional ceramic route. Dense pellets obtained after sintering at different temperatures (1400–1500°C) were characterized by XRD, SEM/EDS, dilatometry (up to 1270°C) and dc electrical conductivity measurements in air (between 200 and 1000°C). The electrical conductivities of all compositions were close to each other and within the range 10−4 S/cm at about 200°C to 1 S/cm at about 1000°C. Arrhenius plots show three different slopes with smooth transitions around 300–350°C and 600–650°C. The activation energy increases from about 50 kJ/mol below 300°C to about 90 kJ/mol between 650 and 1000°C. XRD, SEM/EDS and thermal expansion measurements provided enough evidence on phase and mechanical stability constraints, thus questioning potential technological applications.