Promising ceria–samaria-based nano-oxides for low temperature soot oxidation: a combined study of structure–activity properties

摘要: The design of promising heterogeneous catalysts is an urgent task for protecting the environment from automotive exhaust pollutants. In this work, catalytic efficiency nanosized Ce–Sm and Ce–Sm/γ-Al2O3 samples synthesized using economical coprecipitation deposition methods, respectively, was investigated diesel soot oxidation. physicochemical properties materials were systematically analyzed by means XRD, BET surface area, Raman spectroscopy, TG-DTA, FT-IR HRTEM, ICP-OES, XPS, UV-vis DRS techniques. XRD studies confirmed formation nanocrystalline single-phase oxide solid solutions. HRTEM images showed presence small-sized nanocrystals (∼4–15 nm) in samples. sample exhibited remarkable thermal stability compared with CeO2 samples, as evidenced insignificant variation crystallite size area high temperature treatments. Owing to disparity oxidation state Sm3+ Ce4+, abundant oxygen vacancies formed both Interestingly, vacancy concentration substantially decreased increased calcination temperature, attributed level order activity results revealed that show excellent performance pristine due superior area. A 50% conversion achieved at ∼690, 697 835 K Ce–Sm, calcined 773 K, respectively. It found strongly depends on temperature. Despite its trivial difference respect sample, outstanding vital view practical working conditions engines.