以葡萄糖、尿素、氯化钌和硅溶胶为前驱体,葡萄糖碳化后作为碳模板,利用微波辅助将Ru纳米颗粒限域负载于介孔SiO2之上,焙烧后得到高度均匀分散的Ru-SiO2材料。通过XRD、TEM和BET等表征手段对材料的结构形貌进行了分析,以热催化氨分解反应作为评价体系,对样品进行了催化活性评价。实验表明,此法制备的材料较浸渍法具有更好的催化活性,在相同温度下有更高的转化率。这主要是归因于SiO2载体对活性组分Ru的限域作用,使得Ru颗粒具有较小、均匀的粒径,以及良好的热稳定性。
Using glucose,urea,ruthenium chloride and silica sol as the precursors and carbonized glucose as the carbon template,ruthenium nanoparticles confined within mesoporous silica (Ru-SiO2) with highly dispersion was prepared by microwave-assisted method.The structure and morphology of the materials were characterized by XRD,TEM and BET analysis.The evaluation of catalytic activity of the sample was carried out by thermocatalytic ammonia decomposition reaction.The results showed that the materials prepared by in-situ method exhibited an excellent catalytic activity and higher conversion rate at the same temperature.Combined with the results,this was mainly attributed to the limited action of silica carrier on the active component Ru,which made Ru particles own small and uniform particle size and thermal stability.
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