Dry reforming of methane over bimetallic Ni-Co catalyst prepared from La (CoxNi1-x)(0.5)Fe0.5O3 perovskite precursor: Catalytic activity and coking resistance
Dry reforming of methane over bimetallic Ni-Co catalyst prepared from La (CoxNi1-x)(0.5)Fe0.5O3 perovskite precursor: Catalytic activity and coking resistance
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La(CoxNi1-x)(0.5)Fe0.5O3钙钛矿前驱体制备的双金属Ni-Co催化剂上甲烷的干重整：催化活性和抗结焦性
DOI：
10.1016/j.apcatb.2018.12.072
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Li Ming
中科院分区：
文献类型：
--
作者：
Wang Haiqian;Dong Xiaolei;Zhao Tingting;Yu Haoran;Li Ming
探索高活性、高抗结焦性能的镍基催化剂对于甲烷干重整具有重要意义。通过还原La(CoxNi1-x)0.5Fe0.5O3钙钛矿前驱体制备了La2O3-LaFeO3负载的双金属Ni-Co催化剂。钙钛矿前体采用斜方晶系、菱方晶系晶体结构或两者兼而有之，具体取决于钴含量。通过适量的Co替代，催化活性和抗结焦性能明显增强，这本质上应归因于Ni和Co之间的协同效应。有趣的是，钙钛矿的晶体结构也起着重要作用。 x = 0.10和0.30的斜方钙钛矿前驱体还原的催化剂具有明显更高的结构稳定性，表现出最大的催化活性和抗结焦性。 Co阳离子的多价态和自旋态特征可能会影响钙钛矿结构的稳定性，从而影响钙钛矿中的活性氧物种，从而促进催化活性和沉积碳物种的去除。
Exploring highly active Ni based catalysts with high coking resistance is of great importance for dry reforming of methane. Bimetallic Ni-Co catalysts supported on La2O3-LaFeO3were prepared by reducing La(CoxNi1-x)0.5Fe0.5O3perovskite precursors. The perovskite precursors adopt orthorhombic, rhombohedral crystalline structure, or both, depending on the Co content. The catalytic activity and coking resistance are obviously enhanced by substituting a proper amount of Co, which should be essentially attributed to the synergistic effect between Ni and Co. Interestingly, the crystalline structure of the perovskite also plays an important role. Catalysts reduced from orthorhombic perovskite precursors with x = 0.10 and 0.30 have obvious higher structural stability, which show maximal catalytic activity and coking resistance. The multiple valences and spin states features of Co cations may affect the stability of the perovskite structure, and thus affect the active oxygen species in the perovskite, which promote both the catalytic activity and the removal of deposited carbon species.