Flowerlike Nanosheet-Based High-Entropy Oxides as Catalysts for Aerobic Oxidation of Benzyl Alcohol

Abstract

Aerobic oxidation of benzyl alcohol (BAL) under ambient reaction conditions is a charming goal for the fabrication of high-value oxygenates. However, competent catalysts are presently lacking. Herein, we present a flower-like high entropy oxide (HEO) nanosheet with rich oxygen vacancies for the BAL oxidation by utilizing the high-entropy metal organic framework (HE-MOF) as a precursor. Collective characterizations indicate that the substantial OV and massive pores of HEO facilitate substrate activation, promote mass transfer, and enhance catalytic efficiency. Both experimental results and density functional theory (DFT) simulations clearly illustrate the promoting role of OV in the process for reactant activation, thus significantly contributing to the formation of active oxygen species and driving subsequent oxidation more feasible. This work shines light on structural microenvironmental regulation induced via oxygen-vacancy defect engineering to realize superior selective oxidation catalysis.

Engineering of Pore Design and Oxygen Vacancy on High-Entropy Oxides by a Microenvironment Tailoring Strategy

“…These obstacles result in the agglomeration of catalyst particles, reducing the specific surface area, lower porosity, and limited exposure of active sites, thereby diminishing catalytic performance. To deal with the above obstacles, our group utilized inorganic salts and metal–organic frameworks (MOFs) as templates and precursors to fabricate a series of HEOs with adjustable porosity and active sites. − However, the tedious procedure (removing templates and expensive precursors) significantly hinders its utilization on a large scale. Consequently, developing a low-temperature, rapid synthesis tactic for HEOs with abundant active sites (such as massive oxygen vacancies), rich porosity, and large surface area to boost the catalytic efficiency is imperative.…”

Solvent‐Free Oxidation of Benzyl Alcohol Using Modified Zeolitic Imidazolate Frameworks‐8 (ZIF‐8) Catalysts

“…Appropriate catalyst selection can significantly influence the success of attaining the desired product yield. Some heterogeneous catalysts that have been employed in the alcohol oxidation reaction include AuÀ Pd nanoparticles, [7] perovskite LaMO 3 (M = Cr, Mn, Co, Ni, and Fe), [8] high-entropy oxides (e. g. HP- (FeCrCoNiCu) x O y , HE-MOF, MW-HEO), [9][10][11] Ce Oxysulfate Clusters (MCe 70 , M = Ce, Cu, Ni, Co, and Fe), [12] as well as porous materials like zeolites, [13] nitrogen-doped carbon-encapsulated metallic Co nanoparticles, [14] and Metal-Organic Frameworks (MOFs). [15] Among heterogeneous catalysts, MOFs stand out as porous materials with promising potential across various organic reactions.…”