BaCo_(1-x)Fe_xO_(3-δ)缺陷钙钛矿NO_x储存还原催化剂的制备、结构与性能

Preparation,Structure and Performance of Defected Perovskite BaCo_(1-x)Fe_xO_(3-δ) Catalyst for NO_x Storage and Reduction

制备了B位Fe取代的BaCo1-xFexO3-δ系列缺陷钙钛矿型NOx储存还原(NSR)催化剂,考察了其储存NOx与抗硫性能;应用N2吸附-脱附,X射线衍射,红外光谱,程序升温还原和程序升温脱附等技术对催化剂进行了表征.结果表明,Fe的取代提高了BaCoO3的抗硫能力,当x=0.4时,样品具有相对最大的NOx储存量,且在深度硫化条件下仍保持398μmol/g的NOx储存量,表现出很强的抗硫性能;催化剂性能与其表面晶格氧的活泼性及氧空位的数量密切相关,NOx在BaCo1-xFexO3-δ样品中的储存形式主要为离子态硝酸盐和单齿硝酸盐.

A series of B-site Fe-substituted defected perovskite BaCo1-xFexO3-δ catalyst samples for NOx storage and reduction were pre-pared.The NOx storage and sulfur-resistance performance were investigated.N2 adsorption-desorption,X-ray diffraction,Infrared spectros-copy,temperature-programmed reduction,and temperature-programmed desorption were employed for structural characterization.Fe-substitution can increase the sulfur resistance ability of BaCoO3 perovskite.Among the Fe-substituted samples,the one with x=0.4 shows the largest NOx storage capacity（NSC）.After deep sulfation it still possesses higher NSC（398 μmol/g）,showing strong sulfur resisting ability.The mobility of surface lattice oxygen and the amount of surface oxygen vacancies are highly related to the properties of the catalyst.The NOx is mainly stored as ionic nitrate and monodentate nitrate species in the catalyst.