Poly(ionic liquid)-Modulated Synthesis of Mesoporous Au–Pd Nanospheres for Catalytic Oxidation of <i>p</i>-Hydroxybenzyl Alcohol

Bimetallic nanomaterials with porous structures are appealing to wide attention because of their large specific surface area, open and accessible pores, and free-standing features, but there still remain huge challenges for the green and mild one-pot preparation of well-defined porous bimetallic nanomaterials. Herein, an aqueous synthetic protocol is developed for the one-pot fabrication of mesoporous Au–Pd nanospheres (MNSs) under the regulation of a poly(ionic liquid) 1-butyl-3-methylimidazole polystyrenesulfonate ([Bmim]n[PSS]) at room temperature. The obtained Au–Pd MNSs have uniform spherical morphology, narrow size distribution (45 ± 15 nm), and abundant mesopores. It is shown that [Bmim]n[PSS] serves as structure-directing agent to direct the growth and construction of Au–Pd MNSs. Possessing a large specific surface area, plentiful and open mesopores, and a strong electronic interaction between Au and Pd, Au–Pd MNSs-1 exhibit high catalytic activity, selectivity, and stability in the catalytic oxidation of p-hydroxybenzyl alcohol. Within 60.0 min, p-hydroxybenzyl alcohol can be completely converted and the selectivity toward p-hydroxybenzaldehyde is as high as 100%. After four cycles, 100% selectivity and 88% conversion are still maintained.