Li Liqing, Deng Xin, He Jiani, Zhang Huan, Li Li, Zhu Lihua
College of Chemistry and Chemical Engineering, Jiangxi University of Science and Technology, Jiang Xi, China.
School of Rare Earth and New Materials Engineering, Gannan University of Science and Technology, Jingxi Ganzhou 341000, China.
Dalton Trans. 2023 Dec 5;52(47):17974-17980. doi: 10.1039/d3dt03471b.
Herein, we report that Pd nanoparticles (NPs) anchored on graphitic nitride carbon (Pd/g-CN) catalysts with various Pd contents (1.55 wt%, 0.14 wt%, 0.04 wt%) are successfully prepared a simple NaBH reduction method, exhibiting excellent catalytic activity and selectivity toward 4-aminophenol (4-AP) in 4-nitrophenol (4-NP) selective hydrogenation. 4-NP is completely converted to 4-AP (yield ∼ 100%) under quite moderate reaction conditions (40 °C, 2.0 MPa H and 5 min) over the 1.55 wt% Pd/g-CN catalyst, with a high reaction rate = 134.4 mol mol min. The excellent catalytic performance can be attributed to the following reasons: (1) a higher ratio of Pd(0)/Pd provides much more exposed active sites for the potential adsorption and activation of the reactants, which is beneficial for increasing the reaction rate and catalytic activity; (2) Pd NPs are highly dispersed on g-CN due to the strong interaction of Pd-N or Pd-C; (3) the interfacial synergism effect between Pd NPs and g-CN enables the effective adsorption and activation of H (4-NP) at Pd (g-CN), promoting the catalytic hydrogenation of 4-NP and improving their catalytic properties. In addition, this catalyst has superior reusability.
在此，我们报告通过简单的硼氢化钠还原法成功制备了具有不同钯含量（1.55 wt%、0.14 wt%、0.04 wt%）的负载在石墨氮化碳上的钯纳米颗粒（Pd/g-CN）催化剂，该催化剂在4-硝基苯酚（4-NP）选择性加氢制4-氨基苯酚（4-AP）反应中表现出优异的催化活性和选择性。在相当温和的反应条件（40℃、2.0 MPa氢气和5分钟）下，1.55 wt%的Pd/g-CN催化剂可使4-NP完全转化为4-AP（产率约100%），反应速率较高（k = 134.4 mol mol⁻¹ min⁻¹）。优异的催化性能可归因于以下原因：（1）较高的Pd(0)/Pd比例为反应物的潜在吸附和活化提供了更多暴露的活性位点，有利于提高反应速率和催化活性；（2）由于Pd-N或Pd-C的强相互作用，钯纳米颗粒高度分散在石墨氮化碳上；（3）Pd纳米颗粒与石墨氮化碳之间的界面协同效应使得H₂（4-NP）能够在Pd（g-CN）处有效吸附和活化，促进了4-NP的催化加氢并改善了它们的催化性能。此外，该催化剂具有优异的可重复使用性。
