Unveiling Structural Defects by ¹³⁹La NMR and Raman Spectroscopies at the Origin of Surface Stability for the Design of Cerium-Based Catalysts

Cerium-based complex oxides are essential materials well-suited for numerous applications related to heterogeneous catalysis and electrocatalysis. However, the impact of structural defects on thermal stability surface has still be elucidated. Probing lanthanum environments by 139La NMR analyzing, first time in parallel, associated Raman spectroscopy allow a better view at bulk samples annealed T = 600 1200 °C, respectively. Moreover, we propose another indexing spectra cerium-based compounds with fluorite structure considering two tetrahedral around cationic defects. We evidence existence an unusual isolated La pseudo-cubic site, series cerium-, zirconium-, lanthanum-based oxides. It is found stabilized subsurface farther from surface’s Zr atoms oxygen vacancies. La3+ ions preferentially Zr4+ cations as La2Zr2O7 ternary compound. When this peculiar environment surrounded exclusively Ce4+ cubic sites thermally stable, specific area remains interesting catalytic application high temperatures. enhancing contents tends increase association clusters induce loss area.