Lattice-Refined Transition-Metal Oxides via Ball Milling for Boosted Catalytic Oxidation Performance

Abstract

Surface oxygen vacancy can greatly affect the properties of transition-metal oxides. However, engineering oxygen vacancy-abundant transition-metal oxides with high specific surface area (SSA) remains challenging. At present, the generation of oxygen vacancies in metal oxides is time-consuming and less environmentally friendly by chemical leaching methods that usually require additional waste treatment. Herein, a series of oxygen vacancy-abundant transition-metal oxides with high SSA are constructed via a lattice refining strategy. This strategy is realized by urea-assisted ball milling pyrolysis and is green, efficient, and universal. The oxygen vacancies promote the mobility of oxygen, leading to a boosted catalytic oxidation performance of aromatic sulfides. Such a strategy provides an efficient approach to manufacturing oxygen vacancies on transition-metal oxides, which may be beneficial for various related applications as an effective catalytic material.

Molybdenum Dioxide Nanoparticles Anchored on Nitrogen‐Doped Carbon Nanotubes as Oxidative Desulfurization Catalysts: Role of Electron Transfer in Activity and Reusability

“…It was worth noting that the distribution of rich oxygen vacancies was proposed to be promising active sites in the catalytic ODS reactions. [ 40–42 ]…”

“…It was worth noting that the distribution of rich oxygen vacancies was proposed to be promising active sites in the catalytic ODS reactions. [40][41][42] Hydrogen temperature-programmed reduction (H 2 -TPR) analysis was applied to investigate the reducibility of V O -MoO 2 @NC. As depicted in Figure 4c, both V O -MoO 2 @C and V O -MoO 2 @NC exhibited two main reduction peaks.…”

“…For both the catalytic oxidation of DBT and 4,6-DMDBT, the catalytic oxidation activities of V O -MoO 2 @NC were higher than those of V O -MoO 2 @C, which was attributed to the more abundant oxygen vacancies in V O -MoO 2 @NC. [15,41,53] There are various literatures that have reported the mechanism of ODS when oxygen vacancies act as active sites. [6,42,54] In brief, after the oxidant combines with the oxygen vacancies on the metal oxide via chemical adsorption, the trapped electrons in the oxygen vacancies are transferred to the adsorbed oxidant and further results in the generation of electrophilic species, which are recognized as the driving force for efficient oxidation of thiophenes.…”

Excellent oxidation activity of toluene over core–shell structure Mn2O3@MnO2: role of surface lattice oxygen and Mn species

“…However, the MnO x -1 (N 2 400 °C) catalyst shows the same oxidation efficiency as the MnO x -1 (N 2 300 °C) and MnO x -1 (O 2 300 °C) catalysts in 10 min although the surface lattice oxygen is desorbed from the MnO x -1 (N 2 400 °C) catalyst, which demonstrate that its surface lattice oxygen can be replenished in the oxidation process, confirming that the toluene oxidation follows the Mars-Van Krevelen mechanism for these catalysts. 50,51 These results are strong evidence that surface lattice oxygen plays a crucial role in the oxidation process of toluene.…”

Highly sensitive non-enzymatic hydrogen peroxide monitoring platform based on nanoporous gold via a modified solid-phase reaction method

“…Thus, analytical determination of H 2 O 2 is essential. Currently, there are several available H 2 O 2 -detection techniques such as fluorometry, 4–6 chromatography, 7,8 spectrophotometry, 9,10 chemiluminescence, 11 electrochemistry, 12 titrimetry, 13 and electrochemical methods. 14 The electrochemical methods are among the most effective H 2 O 2 -detection techniques due to their high sensitivity, fast response, and operational simplicity.…”