具有特殊结构和电子性质的PdAu/Al2O3催化剂上蒽醌加氢反应性能

通过改变Pd和Au的负载顺序合成了一系列具有不同结构和电子性质的PdAu双金属催化剂, 并用于蒽醌加氢反应. 其中通过先负载Au后负载Pd的顺序制得的Pd/Au/Al₂O₃催化剂, 其加氢效率可高达14.27 g·L^-1.X射线衍射、透射电子显微镜、H₂程序升温还原和X射线光电子能谱等分析表征结果显示, Pd/Au/Al₂O₃催化剂中分散在Au颗粒表面的Pd纳米颗粒具有独特的爆米花结构, 其表面零价态的单质Pd含量最多, 而这种表面零价态的单质Pd是蒽醌加氢反应中的关键活性组分. 此外, Au的加入可有效抑制副反应的发生, 减少降解产物的生成, 从而大大提高了催化选择性.

Catalytic Performance of PdAu/Al2O3 Catalyst with Special Structural and Electronic Properties in the 2-Ethylanthraquinone Hydrogenation Reaction

A series of bimetallic PdAu catalysts with different structures were prepared by changing the loading sequence of Pd and Au for the hydrogenation of 2-ethylanthraquinone. Pd/Au/Al₂O₃ was obtained by loading Pd onto Au particles deposited onto an Al₂O₃ support with a hydrogenation efficiency up to 14.27 g·L^-1. According to X-ray diffraction, transmission electron microscopy, hydrogen temperature program reduction, and X-ray photoelectron spectroscopy measurements, the popcorn structure and unique electronic properties of the Pd species in the Pd/Au/Al₂O₃ catalyst resulted in the highest content of surface metallic Pd, which was the most active component for the reaction. What is more, the addition of Au can effectively reduce the amount of degradation products by suppressing side reactions.