Effects of calcium substitute in LaMnO_3 perovskites for NO catalytic oxidation  

作　　者：沈美庆 赵真 陈家浩 苏玉更 王军 王欣全 

机构地区：[1]Key Laboratory for Green Chemical Technology of State Education Ministry,School of Chemical Engineering & Technology,Tianjin University [2]State Key Laboratory of Engines,Tianjin University

出　　处：《Journal of Rare Earths》2013年第2期119-123,共5页稀土学报（英文版）

基　　金：Project supported by National High Technology Research and Development Program of China(863Program,2011AA03A405)

摘　　要：La1-x Cax MnO3 （x=0-0.3） perovskite-type oxides were synthesized by citrate sol-gel method. The physical and chemical properties were characterized by X-ray diffraction （XRD）, Brumauer-Emmett-Teller method （BET）, X-ray photoelectron spectroscopy （XPS）, NO＋O2 -TPD （temperature-programmed desorption）, activated oxygen evaluation and H2 -TPR （temperature-programmed reduction） technologies. The results showed that NO catalytic oxidation activity was significantly improved by Ca substitution, especially for lower temperature activity. The La0.9 Ca0.1 MnO 3 sample showed the maximum conversion of 82% at 300 oC. The monodentate nitrates played a crucial role for the formation of NO2 . The reducibility of Mn 4＋ ions and reactivity of activated oxygen were favorable for the catalytic performances of NO oxidation.La1-x Cax MnO3 （x=0-0.3） perovskite-type oxides were synthesized by citrate sol-gel method. The physical and chemical properties were characterized by X-ray diffraction （XRD）, Brumauer-Emmett-Teller method （BET）, X-ray photoelectron spectroscopy （XPS）, NO＋O2 -TPD （temperature-programmed desorption）, activated oxygen evaluation and H2 -TPR （temperature-programmed reduction） technologies. The results showed that NO catalytic oxidation activity was significantly improved by Ca substitution, especially for lower temperature activity. The La0.9 Ca0.1 MnO 3 sample showed the maximum conversion of 82% at 300 oC. The monodentate nitrates played a crucial role for the formation of NO2 . The reducibility of Mn 4＋ ions and reactivity of activated oxygen were favorable for the catalytic performances of NO oxidation.

关 键 词：La 1–x Ca x MnO 3 perovskites NO oxidation monodentate nitrates Mn 4＋ ions activated oxygen 

分 类 号：O643.32[理学—物理化学]