Manipulating the Size and Dispersibility of Cu Species in Confined CuV-HMS Catalysts for Enhanced Catalytic Performance of Toluene Hydroxylation

The size and dispersion of the active metal are crucial for the catalytic activity of metal catalysts. In this study, CuV-HMS-modified catalysts were successfully prepared by introducing Cu–V bimetals into the mesoporous structure using a modified metal micelle template method. The results of particle size calculation based on XRD, H₂-TPR, XPS characterization, and the Debye–Scherrer formula showed that the presence of V species effectively inhibited the agglomeration of CuO nanoparticles, the CuO particle size in the bimetallicmodified catalysts was much smaller, and there was a strong interaction between Cu–V species. Toluene adsorption tests showed that the V species could significantly promote the activation process of toluene adsorption. Combining the properties of Cu species as the main activation center, we propose a bimetallic synergistic catalytic mechanism: the introduction of V species promotes the dispersion of Cu species and enhances the toluene adsorption, whereas Cu species activate H₂O₂ to produce ·OH for the hydroxylation reaction. The catalyst performed optimally at 45% conversion, 25% yield, and a TOF value of 533 h⁻¹. This study provides an important reference for the construction of loaded metal nanoparticles with controllable size and dispersibility with high catalytic activity.