【摘要】 用硝酸盐分解法（N-法）和柠檬酸络合法（L-法）合成了La-Sr-Ni-O系复合氧化物.用XRD技术考察了样品组成、制备条件及灼烧气氛等对产物结构的影响.结果表明:按La_1-xSr_xNiO₃计量比,用N-法合成只能形成四方体心K₂NiF₄结构的A₂BO₄型复合氧化物.而采用L-法,通过改变条件,在0.0≤x≤0.2范围内可形成菱形晶系钙钛矿结构的复合氧化物.另外,用L-法合成La_2-xSr_xNiO₄系列样时发现,制备条件及灼烧温度、气氛对样品结晶态存在较大的影响,高温、空气氛下可形成高结晶态的K₂NiF₄结构复合氧化物.La_2-xSr_xNiO₄体系CO催化氧化活性研究表明,随x(Sr²⁺取代量)增加,CO的转化率增加.更多还原

【Abstract】 La-Sr-Ni-O System oxides were prepared from nitrate Solutions by citric acid-complexing method (L-method) and direct decomposing method (N-method). The effects of sample compositions. Preparation methods and Sintering atmosphere on the products structure of La-Sr-Ni-O systems were characterized by XRD. Results showed that only A2BO4-type oxides with tetragonal K2NiF4 structure can be obtained by N-method for La1_xSrxNiO3 stoichiometrical ratios. Then, within 0.0≤x≤0.2, if the preparative conditions changed, we can get perovskite-type oxide, with Rhombohedral symmetry. Otherwise, for the preparation of La2-xSrxNiO4 through L-method, we found that products crystal state were affected a great deal by preparation conditions such as sintering temperature and atmosphese. Under high temperature and air atmosphere, we can prepare high crystall state oxides with K2NiF4 structure. Results of catalytic activity of La2-xSrxNiO4 System for CO oxidation indicated CO conversion increased with x.更多还原