Crystal and Electronic Structures of CePO₄-Based Proton-Electron Mixed Conductors by Using Synchrotron X-rays

Abstract

We focused on monazite-type Ce(P,V)O4 as a proton-electron mixed conductor, and investigated electrical conduction properties, and crystal and electronic structures by synchrotron X-rays. From conductivity measurements, it was found that the electrical conductivity increased with increasing V content. As for the specimens, we performed X-ray absorption fine structure and synchrotron X-ray diffraction measurements. The XANES spectra demonstrated that an electronic structure of Ce was varied by partially substituting V for P. The maximum entropy method using the diffraction data also indicated that an electron density between Ce and O was increased by the substitution. Such a change of the electronic structure might lead to the improvement of the electrical conduction property.

Pressure-Induced Hexagonal to Monoclinic Phase Transition of Partially Hydrated CePO4

“…Cerium orthophosphate CePO 4 is a material with notable physicochemical properties that has received a fair amount of attention because of its multiple potential real-world applications. Due to mixed electrical conduction properties, CePO 4 has been proposed as a promising material for intermediate temperature fuel-cell and oxygen sensors applications. − Photoluminescent terbium-doped CePO 4 is used in the fabrication of sensors for the detection of O 2 , Fe 2+ , Co 2+ , and glucose. − Moreover, being a chemically stable material, CePO 4 is also a promising alternative to ZnO and TiO 2 in sunscreen filters for the protection of human skin from UV rays , and as a better additive for improved corrosion resistance of Ni–P coatings …”