Ma Yongde, Li Shusheng, Zhang Tianhua, Zhang Yangyu, Wang Xiuyun, Xiao Yihong, Zhan Yingying, Jiang Lilong
National Engineering Research Center of Chemical Fertilizer Catalyst, Fuzhou University, Fuzhou, Fujian 350002, China.
Nanoscale. 2021 Mar 12;13(9):5026-5032. doi: 10.1039/d0nr08723h.
Catalytic combustion is a promising way to remove trace amounts of CH4 to alleviate serious environmental concerns. However, the reactivity of a catalyst at low temperature is usually limited because of the difficulty to activate the C-H bond of methane. Herein, we design a Pd(PdO)/Co3O4@SiO2 bimetallic oxide core-shell catalyst which shows much higher activity in the methane combustion reaction compared with Pd(PdO)/SiO2 and Co3O4@SiO2 catalysts without a core-shell structure. The T50% and T90% of Pd(PdO)/Co3O4@SiO2 are 357 °C and 445 °C, respectively, which decrease by 67 °C and 55 °C in comparison with those of Pd(PdO)/SiO2. Extensive characterization demonstrates that the bimetallic oxide core-shell structure can effectively enhance the metal interaction between Pd and Co, which can weaken the strength of the Co-O bond in Pd(PdO)/Co3O4@SiO2. The weakening of the Co-O bond could promote the release of more lattice oxygen species to participate in the C-H breaking, resulting in superior catalytic performance in methane combustion at low temperature.
催化燃烧是去除痕量CH4以缓解严重环境问题的一种有前景的方法。然而，由于难以活化甲烷的C-H键，催化剂在低温下的反应活性通常受到限制。在此，我们设计了一种Pd(PdO)/Co3O4@SiO2双金属氧化物核壳催化剂，与没有核壳结构的Pd(PdO)/SiO2和Co3O4@SiO2催化剂相比，它在甲烷燃烧反应中表现出更高的活性。Pd(PdO)/Co3O4@SiO2的T50%和T90%分别为357℃和445℃，与Pd(PdO)/SiO2相比分别降低了67℃和55℃。广泛的表征表明，双金属氧化物核壳结构可以有效地增强Pd和Co之间的金属相互作用，这可以削弱Pd(PdO)/Co3O4@SiO2中Co-O键的强度。Co-O键的削弱可以促进更多晶格氧物种的释放以参与C-H键的断裂，从而在低温甲烷燃烧中表现出优异的催化性能。
