高温稳定的三明治结构介孔负载型贵金属纳米材料催化剂

项目名称： 高温稳定的三明治结构介孔负载型贵金属纳米材料催化剂

项目编号： No.21301138

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 高传博

作者单位： 西安交通大学

项目金额： 25万元

中文摘要： 贵金属纳米粒子由于其优异的反应活性给工业催化带来了崭新的可能性。但由于其具有巨大的表面能，贵金属纳米粒子极易发生团聚烧结现象而丧失催化活性。因此，提高贵金属纳米粒子的稳定性和抗烧结能力成为一项紧迫而极富挑战性的研究课题。根据文献报道，已有部分研究工作在此领域有了长足的进展，但在高温等严苛条件下贵金属纳米粒子的稳定性和抗烧结能力仍有待进一步提高。为达到此目的，本项目旨在开发一种新型的贵金属纳米粒子负载策略，拟采用高比表面积的介孔二氧化硅材料作为贵金属纳米粒子的载体，通过在介孔中构建SiO2/Metal/C三明治结构使贵金属纳米粒子负载到SiO2和碳的夹层结构中，以期限制贵金属纳米粒子的熟化和迁移聚结，提高材料在严苛条件下的抗烧结能力。该课题的设立和顺利实施，一方面可促进介孔微反应器的特性研究和定向设计的研究，另一方面也有望为当前燃料电池和CO氧化等实际应用提供一套制备稳定高效催化剂的新方案。

中文关键词： 贵金属纳米粒子；超小尺寸；纳米催化；稳定化策略；尺寸效应

英文摘要： Noble metal nanoparticles open up new opportunities in industrial catalysis due to their superior reactivity. However, they are heavily prone to aggregate and sinter as a result of their high surface energy, leading to a drastic loss of catalytic reactivity. In this regard, it becomes an urgent yet challenging concern to improve the stability of the noble metal nanoparticles with enhanced resistance to sintering. There have been a few efforts in literature to achieve this goal which proves effective in many circumstances. However, the stability of the noble metal nanoparticles is still unsatisfactorily low under even harsh conditions, for example, at a high temperature, which leaves a lot of room in this field to develop alternative stabilizing methods. This proposal aims at developing a novel stabilizing strategy for noble metal nanoparticles, employing mesoporous silica which has high surface area as an appropriate support. In our design, a SiO2/Metal/C architecture is built in the mesopores of the mesoporous silica, with noble metal nanoparticles sandwiched in between layers of silica and carbon. It is expected that Ostwald ripening and interparticle coalescence of the noble metal nanoparticles in the sandwiched space are highly suppressed, which results in significantly enhanced stability of the noble metal

英文关键词： Noble metal nanoparticles；Ultrasmall size；Nano-catalysis；Stabilization strategy；Size effect