Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
Área Departamental de Engenharia Química, ISEL, Instituto Politécnico de Lisboa, 1959-007 Lisboa, Portugal.
Molecules. 2020 Jun 26;25(12):2951. doi: 10.3390/molecules25122951.
Pd(II) and Pt(II) composites with activated carbon (AC), graphene oxide, and multiwalled carbon nanotubes were prepared by ball milling and used as catalysts for the Suzuki-Miyaura reaction, under several energy inputs (mechanical grinding, conventional heating, and microwave irradiation). The catalytic composites were characterized by ICP-MS, BET, XPS analyses, TEM, and SEM. The average particle size of the prepared composites was estimated to be in the range of 6-30 nm, while the loadings of Pd and Pt did not significantly affect the surface area of the AC support due to the tendency to agglomerate as observed by the TEM analysis. The Pd/AC composites exhibit high mechanochemical catalytic activity in cross-coupling of bromobenzene and phenylboronic acid with molar yields up to 80% with TON and TOF of 222 and 444 h, respectively, achieved with Pd(4.7 wt%)-AC catalyst under the liquid assisted grinding for 0.5 h at ambient conditions, using cyclohexene as an additive.
Pd(II) 和 Pt(II) 复合材料与活性炭 (AC)、氧化石墨烯和多壁碳纳米管通过球磨制备，并用作铃木-宫浦反应的催化剂，在几种能量输入（机械研磨、常规加热和微波辐射）下。通过 ICP-MS、BET、XPS 分析、TEM 和 SEM 对催化复合材料进行了表征。制备的复合材料的平均粒径估计在 6-30nm 范围内，而 Pd 和 Pt 的负载量由于 TEM 分析观察到的团聚趋势，对 AC 载体的表面积没有显著影响。Pd/AC 复合材料在溴苯和苯硼酸的交叉偶联中表现出高机械化学催化活性，摩尔产率高达 80%，使用 Pd(4.7wt%)-AC 催化剂，在环境条件下使用环己烯作为添加剂，在液体辅助研磨 0.5 小时后，TON 和 TOF 分别达到 222 和 444h。
