Composition and Electronic Structure of LaO/CNFs@C Core-Shell Nanoparticles with Variable Oxygen Content.

LaO nanoparticles stabilized on carbon nanoflake (CNF) matrix were synthesized and graphitized to produce core-shell structures LaO/CNFs@C. Further oxidation of these structures by nitric acid vapors for 1, 3 or 6 h was performed, and surface-oxidized particles LaO/CNFs@C_x (x = 1, 3, 6) were produced. Bulk and surface compositions of LaO/CNFs@C and LaO/CNFs@C_x were investigated by thermogravimetric analysis and X-ray photoelectron spectroscopy.