摘要
研究了La_(1-x)Sr_xNiO_(3-λ)(0≤x≤1)系列催化剂的固态性质与催化氨氧化反应性能的关系。发现在LaNiO_3中掺入Sr^(2+),在x≤0.3的范围内,催化剂保持钙钛石结构不变,但晶格发生了较大的畸变,氧空位有序化程度提高;在X>0.3的范围内,钙钛石结构逐步被破坏,出现La_2NiO_4相。此系列催化剂用于氨氧化反应,Ni^(3+)是主要的活性离子,O^-或O_2^(2-)离子为主要活性氧种,反应遵循Redox机理。
The relationship between the physico-chemical properties and the catalytic activity for ammonia oxidation of catalysts La1-xSrxNiO3-λ has been studied. The mixed oxides La1-xSrxNiO3-λ could keep the single phase of perovskite type structure when x≤0.3, the ordering level of oxygen vacancy increased with increasing the x value, but the concentration of Ni3+ decreased. While in the case of x higher than 0.3, the La2NiO4 phase appeared together with the perovskite phase. The active phase for ammonia oxidation is the perovskite type phase, the active sites are Ni3+ . The reaction follows the redox mechanism.
