The proton-conducting electrolyte is a key component for solid oxide electrochemical cells for delivering high-efficient hydrogen production or electricity generation. BaZrO₃-based materials have been widely used due to their high proton conductivity and chemical stability. However, some issues such as low performance and electronic leakage can affect their application. In this work, we introduced a type of B-site dopant to induce higher proton concentration in BaZrO₃. The proton conduction and hydration behavior as a function of dopant level are studied and compared with the conventional benchmarking electrolyte, 20 mol% yttrium doped BaZrO₃ (BZY20). The underlaying mechanism for achieving a higher level of hydration is investigated by various spectroscopy techniques. The electrochemical performances are also evaluated to compare the electrolysis performance and Faradaic efficiency of p-SOEC at different operating conditions to prove the feasibility of using this new electrolyte composition.