Surface-Engineered Homostructure for Enhancing Proton Transport

Ultra-wide bandgap semiconductor samarium oxide attracts great interest because of its high stability and electronic properties. However, the ionic transport properties of Sm₂ O₃ have rarely been studied. In this work, Ni doping is proposed to be used for electronic structure engineering of Sm₂ O₃ . The formation of Ni-doping defects lowers the Fermi level to induce a local electric field, which greatly enhances the proton transport at the surface. Furthermore, ascribed to surface modification, the high concentration of vacancies and lattice disorder on the surface layer promote proton transport. A high-performance of 1438 mW cm^-2 and ionic conductivity of 0.34 S cm^-1 at 550 °C have been achieved using 3% mol Ni doped Sm₂ O₃ as electrolyte for fuel cells. The well-dispersed Ni doped surface in Sm₂ O₃ builds up continuous surfaces as proton channels for high-speed transport. In this work, a new methodology is presented to develop high-performance, low-temperature ceramic fuel cells.