Single Mo Atoms Stabilized on High-Entropy Perovskite Oxide: A Frontier for Aerobic Oxidative Desulfurization

Abstract

The design and preparation of catalysts with both excellent stability and maximum exposure of catalytic active sites is highly desirable; however, it remains challenging in heterogeneous catalysis. Herein, a entropy-stabilized single-site Mo catalyst via a high-entropy perovskite oxide LaMn 0.2 Fe 0.2 Co 0.2 Ni 0.2 Cu 0.2 O 3 (HEPO) with abundant mesoporous structures was initiated by a sacrificial-template strategy. The presence of electrostatic interaction between graphene oxide and metal precursors effectively inhibits the agglomeration of precursor nanoparticles in a high-temperature calcination process, thereby endowing the atomically dispersed Mo 6+ coordinated with four O atoms on the defective sites of HEPO. The unique structure of single-site Mo atoms' random distribution with an atomic scale greatly enriches the oxygen vacancy and increases surface exposure of the catalytic active sites on the Mo/HEPO-SAC catalyst. As a result, the obtained Mo/HEPO-SAC exhibits robust recycling stability and ultra-high oxidation activity (turnover frequency = 3.28 × 10 −2 ) for the catalytic removal of dibenzothiophene (DBT) with air as the oxidant, which represents the top level and is strikingly higher than the state-of-the-art oxidation desulfurization catalysts reported previously under the same or similar reaction conditions. Therefore, the finding here for the first time expands the application of single-atom Mo-supported HEPO materials into the field of ultra-deep oxidative desulfurization.

Crystal-Plane-Engineered TiO2-Anchored Vanadium Single Atoms and Clusters for Boosting Ultradeep Aerobic Oxidative Desulfurization of Diesel

“…In this AODS process, the aromatic sulfides are catalytically oxidized to be their corresponding sulfone compounds, which are the intermediates for the fabrication of high-economic-value semiconductors and pharmaceutical materials. , Therefore, the catalytic oxidative activity is extremely important for the AODS catalyst in this process. Thus far, a variety of AODS catalysts, such as metal oxides, , 2D materials, , polyoxometalates, , and supported ionic liquids, , have been investigated for the AODS of aromatic sulfides from diesel. Therein, titanium dioxide (TiO 2 )-supported catalysts have drawn ever-increasing interest by virtue of their distinctive physicochemical property and low cost. − Xiao and co-authors proposed that the size of TiO 2 particles exerted an important effect on the desulfurization performance of diesel and that the catalyst with the smaller TiO 2 particle size exhibits higher desulfurization performance due to its shorter diffusion path and larger external surface area .…”

Improvement of the Oxidative Desulfurization Performance Using MoO3/CuO‐Modified Hierarchical HY Zeolite

“…[19] Liu and coworkers investigated ultra-deep aerobic oxidative desulfurization of diesel using V 2 O 5 /TiO 2 and a single Mo atom on perovskite oxide. [20,21] Other works have explored supported metal oxides such as VO 2 , WO 3 , MoO 3 , NiMo/Al 2 O 3 , and Mo/ SiO 2 . [22][23][24][25] Motivated by the above work, hierarchical Y zeolite was prepared at first using NH 4 OH to the formation of mesoporosity to minimize framework damage in the presence of the CTAB template.…”