当前位置: X-MOL 学术Catal. Sci. Technol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Porous Mn-based oxides for complete ethanol and toluene catalytic oxidation: the relationship between structure and performance
Catalysis Science & Technology ( IF 4.4 ) Pub Date : 2020/02/10 , DOI: 10.1039/c9cy02522g
Shaohua Chen 1, 2, 3, 4, 5 , Hui Li 6, 7, 8, 9 , Yu Hao 1, 2, 3, 4, 5 , Rui Chen 1, 2, 3, 4, 5 , Tiehong Chen 1, 2, 3, 4, 5
Affiliation  

A series of porous Mn-based oxides (mullite SmMn2O5, perovskite SmMnO3, spinel Mn3O4 and bixbyite Mn2O3) were systematically prepared and applied in ethanol and toluene catalytic oxidation. Among them, SmMn2O5 exhibited the highest catalytic activity, the best hydrothermal stability and the highest durability. Due to the different compositions and structures of the catalysts, the surface composition, Mn-valence state, reduction properties, and adsorption and desorption behavior of oxygen and ethanol were different as characterized by XPS, H2-TPR, O2-TPD and ethanol-TPD measurements. Based on the characterization results, the relationship between the catalyst structure (crystal and electronic structure) and catalytic activity was discussed in terms of their crystal field configurations and structures of the energy bands. The superior activity of SmMn2O5 could be attributed to dz2 orbital occupancy near the Fermi level determined by the Mn3+-centered pyramidal field, as well as the existence of a Mn3+–Mn3+ dimeric structure, which is critical for C–C bond cleavage.

中文翻译:

用于完全乙醇和甲苯催化氧化的多孔锰基氧化物:结构与性能之间的关系

系统地制备了一系列多孔锰基氧化物(莫来石SmMn 2 O 5,钙钛矿SmMnO 3,尖晶石Mn 3 O 4和方铁锰矿Mn 2 O 3),并将其应用于乙醇和甲苯催化氧化。其中,SmMn 2 O 5表现出最高的催化活性,最佳的水热稳定性和最高的耐久性。由于催化剂的组成和结构不同,XPS,H 2 -TPR,O 2表征其表面组成,Mn价态,还原性能以及氧和乙醇的吸附和解吸行为均不同。-TPD和乙醇-TPD测量。根据表征结果,从催化剂的晶体结构和能带结构的角度,探讨了催化剂结构(晶体和电子结构)与催化活性之间的关系。SmMn 2 O 5的优异活性可归因于以Mn 3+为中心的锥体区域确定的费米能级附近的d z 2轨道占有率,以及Mn 3+ -Mn 3+二聚体结构的存在。对于CC键断裂至关重要。
更新日期:2020-03-26
down
wechat
bug