Protonic ceramic electrolysis cells for fuel production: a brief review

Proton-conducting oxides exhibit significant hydrogen ion (proton) conductivity at intermediate temperatures around 300–600 °C. Owing to their distinguished features compared to high-temperature oxygen ion-conducting oxide electrolytes and low-temperature proton-conducting polymer electrolytes, diverse electrochemical applications based on the proton-conducting oxides have attracted great attention for efficient energy conversions. This review particularly aims to introduce protonic ceramic electrolysis cells (PCECs) and their extended applications. The constituent materials, recent developments, remaining issues in PCECs as well as the application integrated with PCEC for electrochemical ammonia synthesis will be presented. In addition, for each section, the relevant prospects and recommendations for future research directions will be discussed.