Deboos Victor, Calabrese Carla, Giraudon Jean-Marc, Morent Rino, De Geyter Nathalie, Liotta Leonarda Francesca, Lamonier Jean-François
Unité de Catalyse et Chimie du Solide (UCCS), Université de Lille, CNRS, Centrale Lille, Université Artois, UMR 8181, 59000 Lille, France.
Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering and Architecture, Ghent University, 9000 Ghent, Belgium.
Nanomaterials (Basel). 2023 Jul 28;13(15):2202. doi: 10.3390/nano13152202.
Cu (10 wt%) materials on silica nanotubes were prepared via two different synthetic approaches, co-synthesis and wetness impregnation on preformed SiO nanotubes, both as dried or calcined materials, with Cu(NO)2.5HO as a material precursor. The obtained silica and the Cu samples, after calcination at 550 °C for 5 h, were characterized by several techniques, such as TEM, N physisorption, XRD, Raman, H-TPR and XPS, and tested for toluene oxidation in the 20-450 °C temperature range. A reference sample, Cu(10 wt%) over commercial silica, was also prepared. The copper-based silica nanotubes exhibited the best performances with respect to toluene oxidation. The Cu-based catalyst using dried silica nanotubes has the lowest T (306 °C), the temperature required for 50% toluene conversion, compared with a T of 345 °C obtained for the reference catalyst. The excellent catalytic properties of this catalyst were ascribed to the presence of easy copper (II) species finely dispersed (crystallite size of 13 nm) on the surface of silica nanotubes. The present data underlined the impact of the synthetic method on the catalyst properties and oxidation activity.
通过两种不同的合成方法制备了负载在二氧化硅纳米管上的铜（10重量%）材料，即共合成法以及在预先形成的二氧化硅纳米管上进行湿浸渍法，两种方法所制得的材料均为干燥态或煅烧态，以硝酸铜·2.5水合物作为原料前驱体。将所制得的二氧化硅和铜样品在550℃下煅烧5小时后，采用多种技术进行表征，如透射电子显微镜（TEM）、氮气物理吸附、X射线衍射（XRD）、拉曼光谱、氢气程序升温还原（H-TPR）和X射线光电子能谱（XPS），并在20 - 450℃温度范围内对甲苯氧化进行测试。还制备了一个参考样品，即商业二氧化硅负载10重量%的铜。在甲苯氧化方面，铜基二氧化硅纳米管表现出最佳性能。与参考催化剂的50%甲苯转化率所需温度345℃相比，使用干燥二氧化硅纳米管的铜基催化剂的最低甲苯转化率温度（T₅₀）为306℃。该催化剂优异的催化性能归因于在二氧化硅纳米管表面存在精细分散的易还原铜（II）物种（微晶尺寸为13纳米）。目前的数据强调了合成方法对催化剂性能和氧化活性的影响。
