The phase composition and electrochemical performance of CaZr1−xYbxO3−δ proton conductor

To study the electrochemical properties of Yb-doped CaZrO 3 in more detail, the CaZr 1 −x Yb x O 3 −δ ( x  = 0.000, 0.025, 0.050, 0.075, and 0.100) solid electrolyte specimens were prepared by high-temperature solid-state method at the temperatures of 1523 K and 1873 K for 8 h. XRD, SEM, EDS, and electrochemical workstation were used to test the micromorphology and electrochemical performance of the electrolyte samples. When the doping amount of Yb is 0.05, the electrolyte sample has excellent electrical properties. The total conductivity of electrolyte CaZr 0.95 Yb 0.5 O 3 − δ is 1.13 × 10 −5 to 1.28 × 10 −3 S/cm and the conductivity activation energy falls in 0.69–1.34 eV in hydrogen and oxygen atmosphere at 973–1173 K. The chemical diffusion coefficient of hydrogen in CaZr 0.95 Yb 0.05 O 3 −δ electrolyte is between 1.55 × 10 −6 and 5.82 × 10 −6 cm 2 /s in the temperature range of 973 to 1373 K, and the diffusion activation energy is 12,278 kJ/mol.