单壁碳纳米管作支撑的杂化金纳米催化剂比TiO2和炭黑具有更优氧化芳香醇的性能

摘要

Gold nanocomposites based on three supports, single wall carbon nanotubes, carbon black and TiO2, were prepared using an in-situ reduction technique and characterized.They were tested for their suitability as heterogeneous catalysts in the green aerobic oxidation of 1-phenylethanol, 2-phenylethanol and benzylalcohol of industrial importance.For all reactions, the use of single wall carbon nanotubes as supports resulted in superior reaction efficiency and specificity for aldehyde to that of TiO2 and carbon black.The gold nanocatalysts can be reused over several reaction cycles with a minimal degeneration in catalytic activity.The activity of the gold nanoparticle catalyst was related to the shape and size of the gold particles and the properties of the support.The selectivity was ascribed to the functional groups on the substrate, the properties of the supports and the particle size distributions of the gold nanoparticles.%采用原位还原技术制备出以单壁碳纳米管、炭黑(P90)和TiO2为支撑的3种金纳米复合材料,并通过多种表征手段来探讨物理性能.再将他们作为1-苯基乙醇、2-苯基乙醇和苯甲醇的绿色需氧氧化杂化催化剂来测试稳定性.在所有反应中,与P90和TiO2相比,以单壁碳纳米管作支撑的金纳米杂化催化剂呈现出最优的反应效率和特异性.这些金纳米杂化催化剂经多次反应循环后反应活性衰减很小,从而能被重复使用.同时探讨了金纳米杂化催化剂活性高的原因,包括颗粒形貌、尺寸和支撑体性能.可以推断,基底上功能团迁移的位置、支撑材料的性质和活性金纳米颗粒相的颗粒尺寸分布均有助于使这些催化剂在反应中显示出高的选择性.