复合氧化物La_(1-x)Ba_xCoO_3对NO直接分解的研究

Direct decomposition of NO into N_2 and O_2 over La_(1-x)Ba_xCoO_3 perovskite oxide

采用柠檬酸络合法合成了La1-xBaxCoO3(x=0,0.1,0.2,0.3)系列钙钛矿型氧化物催化剂。考察了催化剂分解NO的催化活性。结果表明,掺杂量为0.2时分解NO活性最佳,850℃时,催化分解NO为N2的转化率达到69.6%。O2-TPD和H2-TPR测试结果表明:掺入少量的Ba有利于氧空位的还原和迁移,增强了钴离子的氧化还原性能,可使催化剂分解NO的催化活性明显提高。

The perovskite La1-xBaxCoO3 （x = 0. 1,0.2,0.3 ） catalysts were prepared by citric acid sol- gel method. The activity of NO direct decomposition over these catalysts have been investigated, the results show that Lao.s Ba0.2CoO3 is the most active. NO conversion increases with reaction temperature, and at 1 123 K, NO conversion to N2 attained values of 69.6%. O2 - TPD and H2 - TPR results show that doping small Ba at La site of LaCoO3 is favorable in reducing and moving of oxygen vacancy, which enhancing the redox ability of cobalt ion and increasing the NO decomposition activity.