Alumina-Supported Ternary Palladium–Boron–Phosphorus Mesoporous Alloy Nanospheres as Nitrobenzene Hydrogenation Catalysts

Abstract

In this work, we first report the use of palladium−boron−phosphorus (PdBP) ternary alloys as highly efficient nitrobenzene hydrogenation catalysts, where these alloys feature mesoporous and metal−metalloid−nonmetal ternary alloy nanostructures. The mentioned mesoporous PdBP alloys (m-PdBP) were synthesized by a one-pot aqueous coreduction method followed by loading them on alumina to obtain m-PdBP/Al 2 O 3 nanocatalysts. At 45 °C, a nitrobenzene/Pd molar ratio of 2500/1 and atmospheric hydrogen pressure, m-PdBP/Al 2 O 3 could achieve 98% conversion of nitrobenzene at the a reaction time of 30 min. m-PdBP/Al 2 O 3 is comparable to state-of-the-art Pd-based catalysts for nitrobenzene hydrogenation at atmospheric hydrogen pressure. Characterizations and theoretical calculations indicate that the improvement of catalytic performance can be attributed to the alloying effect of the incorporation of B and P into palladium, which facilitates the desorption of aniline and thus promotes the hydrogenation activity.