Matveyeva Anna N, Omarov Shamil O, Gavrilova Marianna A, Sladkovskiy Dmitry A, Murzin Dmitry Yu
Laboratory of Materials and Processes for Hydrogen Energy, Ioffe Institute, Politekhnicheskaya ul. 28, 194021 St. Petersburg, Russia.
Resource-Saving Department, St. Petersburg State Institute of Technology (Technical University), Moskovskiy pr. 26, 190013 St. Petersburg, Russia.
Materials (Basel). 2022 Nov 11;15(22):7970. doi: 10.3390/ma15227970.
Rare-earth orthoferrites have found wide application in thermocatalytic reduction-oxidation processes. Much less attention has been paid, however, to the production of CeFeO, as well as to the study of its physicochemical and catalytic properties, in particular, in the promising process of CO utilization by hydrogenation to CO and hydrocarbons. This study presents the results of a study on the synthesis of CeFeO by solution combustion synthesis (SCS) using various fuels, fuel-to-oxidizer ratios, and additives. The SCS products were characterized by XRD, FTIR, N-physisorption, SEM, DTA-TGA, and H-TPR. It has been established that glycine provides the best yield of CeFeO, while the addition of NHNO promotes an increase in the amount of CeFeO by 7-12 wt%. In addition, the synthesis of CeFeO with the participation of NHNO makes it possible to surpass the activity of the CeO-FeO system at low temperatures (300-400 °C), as well as to increase selectivity to hydrocarbons. The observed effects are due to the increased gas evolution and ejection of reactive FeO nanoparticles on the surface of crystallites, and an increase in the surface defects. CeFeO obtained in this study allows for achieving higher CO conversion compared to LaFeO at 600 °C.
稀土正铁酸盐已在热催化还原-氧化过程中得到广泛应用。然而，对于CeFeO的制备及其物理化学和催化性能的研究却很少受到关注，特别是在通过加氢转化为CO和碳氢化合物这一有前景的CO利用过程中。本研究展示了使用各种燃料、燃料与氧化剂比例以及添加剂通过溶液燃烧合成（SCS）法合成CeFeO的研究结果。通过XRD、FTIR、N-物理吸附、SEM、DTA-TGA和H-TPR对SCS产物进行了表征。已确定甘氨酸能使CeFeO的产率最高，而添加NHNO可使CeFeO的量增加7-12 wt%。此外，在NHNO参与下合成CeFeO能够在低温（300-400°C）下超过CeO-FeO体系的活性，同时提高对碳氢化合物的选择性。观察到的这些效应归因于气体逸出增加、微晶表面活性FeO纳米颗粒的喷出以及表面缺陷的增加。本研究中获得的CeFeO在600°C时比LaFeO具有更高的CO转化率。
