High-Performance Sr and Mg Co-Doped LaAlO 3 Proton Conducting Electrolyte for Semiconductor Ion Fuel Cells

作者：Jiangyu Yu, Yingbo Zhang, Decai Zhu, Wenliang Fan, Nan Wang, Yaohui Niu, Jiali Zhou, Chengjun Zhu · 发表于：The Journal of Physical Chemistry C · 年份：2025 · DOI：10.1021/acs.jpcc.5c00591 · 被引用次数：4 · 研究领域：Advancements in Solid Oxide Fuel Cells、Fuel Cells and Related Materials、Electronic and Structural Properties of Oxides

A major challenge for semiconductor ion fuel cells (SIFCs) is to design an electrolyte with proton transport properties so that it can maintain high ionic conductivity within relatively low temperatures. Herein, we develop a Sr and Mg codoped LaAlO 3 electrolyte that facilitates efficient conduction of protons and oxygen ions by enriching oxygen vacancies and reducing the activation energy of ion conduction. The optimized electrolyte shows a low activation energy of 0.31 eV and demonstrates remarkably elevated ionic conductivity at low temperatures, e.g., 0.1994 S cm –1 at 550 °C. This is attributed to the significant increase in oxygen vacancies, which has been verified by XPS technology. Meanwhile, the Sr and Mg codoped LaAlO 3 electrolyte exhibits remarkable proton transport properties, confirmed by proton filtration experiments, which provide further evidence for the improvement of the electrolyte ionic conductivity. As a result, the fuel cell with an optimized LaAlO 3 electrolyte delivers an impressive peak power density of 977 mW·cm –2 with an open circuit voltage (OCV) of 1.126 V at 550 °C. Particularly, compared with the fuel cell with a pure LaAlO 3 electrolyte, the peak power density is increased by 38.4%. The dual-ion doping strategy provides crucial insight into the further development of high ionic conductivity electrolytes for SIFCs.