Chen Haipeng, Liu Pei, Li Jiaqi, Wang Yuanjie, She Chenxing, Liu Jinqiang, Zhang Linbao, Yang Qingfeng, Zhou Shixue, Feng Xun
Henan Key Laboratory of Function-Oriented Porous Materials , Luoyang Normal University , Luoyang 471934 , China.
State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology , Shandong University of Science and Technology , Qingdao 266590 , China.
ACS Appl Mater Interfaces. 2019 Aug 28;11(34):31009-31017. doi: 10.1021/acsami.9b11285. Epub 2019 Aug 13.
Thermal conversion of CO to value-added chemicals is challenging due to the extreme inertness of the CO molecule and the low selectivity of products. We reported a defect-rich MgH/CuO hydrogen storage composite from mechanochemical ball-milling for the catalytic hydrogenation of CO to lower olefins. The defect-rich MgH/CuO hydrogen storage composite achieves a C-C selectivity of 54.8% and a CO conversion of 20.7% at 350 °C under a low H/CO ratio of 1:5, which increases the efficiency of H utilization by offering lattice H species for hydrogenation. Density functional theory calculations show that the defective structure of MgH/CuO can promote CO molecule adsorption and activation, while the electronic structure of MgH is beneficial for offering lattice H for CO molecule hydrogenation. The lattice H can combine the C site of CO molecule to promote the formation of Mg formate, which can be further hydrogenated to lower olefins under a low H concentration. This work for CO conversion by a defect-rich MgH/CuO hydrogen storage composite can inspire the catalysts design for the hydrogenation of CO to lower olefins.
由于CO分子的极端惰性和产物的低选择性，将CO热转化为高附加值化学品具有挑战性。我们报道了一种通过机械化学球磨制备的富含缺陷的MgH/CuO储氢复合材料，用于将CO催化氢化为低级烯烃。这种富含缺陷的MgH/CuO储氢复合材料在350℃、低H/CO比为1:5的条件下，C-C选择性达到54.8%，CO转化率达到20.7%，通过提供晶格H物种用于氢化提高了H的利用效率。密度泛函理论计算表明，MgH/CuO的缺陷结构可以促进CO分子的吸附和活化，而MgH的电子结构有利于为CO分子氢化提供晶格H。晶格H可以与CO分子的C位点结合，促进甲酸镁的形成，在低H浓度下，甲酸镁可以进一步氢化为低级烯烃。这项关于通过富含缺陷的MgH/CuO储氢复合材料进行CO转化的工作可以启发用于将CO氢化为低级烯烃的催化剂设计。
