纳米石墨烯壳层稳定金属催化剂的制备及催化特性研究

Nanocarbon supported metal catalysts play an important role in the industrial catalysis. Recently, with the development of the graphene nanomaterials, the graphene supported metal catalyts with excellent catalytic performance have become a hot research field. However, how to fabricate a high reactivity graphene supported metal catalyst and understanding its intrinsic catalytic mechanism is still a challenge. In this project, we will design a model nanocarbon support with a novel core-shell structure. This model nanocarbon support is composed by a nanodiamond core and one or two layer ultra-thin graphene nanoshell. Combing with the XAFS, HRTEM，catalytic performance and the DFT calculation, we want to study the interaction between the metal nanoparticles and graphene nanoshell, and its affect in the catalytic performance. Hopefully, we can understand the intrinsic catalytic mechanism of graphene nanoshell supported metal catalysts at atom or molecular level, and try to explore a new way to design novel nanocarbon supported metal catalysts.

纳米碳材料负载金属催化剂在催化领域起着十分重要的作用，近年来随着石墨烯材料的出现及不断发展，石墨烯负载金属催化剂表现出的优异性能受到人们的广泛关注，然而如何构造和制备高活性的石墨烯负载金属催化剂并深入理解其催化作用本质依然是一个具有挑战性的课题。本课题拟设计和制备一种具有核壳结构的模型石墨烯载体，该载体以纳米金刚石为核，1-2层石墨烯为壳，利用该模型载体研究石墨烯与Pd纳米粒子之间的相互作用以及对CO催化氧化性能的影响， 考察石墨烯载体的壳层层数、表面结构、掺杂原子的种类和数量对Pd纳米粒子的粒径分布、形貌、结构、电子特性以及对CO分子吸附能力的影响，利用XAFS、HRTEM等表征手段结合催化性能测试和理论计算结果，在原子和分子水平上理解模型石墨烯载体与Pd纳米粒子之间的催化作用本质，为新型石墨烯负载金属催化剂的探索与制备开辟一条新的途径。

为了设计高活性和高稳定性的纳米碳负载金属纳米粒子催化剂，本项目以一种具有复合结构的模型纳米石墨烯材料为模型载体，该材料以纳米金刚石为核，少层石墨烯为壳。通过本项目的实施，实现了该复合碳材料的可控制备。同时利用该材料为模型载体来负载金属纳米粒子（钯、铂等金属），通过系统研究发现利用该纳米碳载体表面的碳缺陷与金属纳米粒子表面原子作用形成的金属-碳键，能够显著增强了负载型金属纳米粒子在高温多相催化反应中的活性和稳定性，为开发新型纳米碳材料负载型金属催化剂的设计提供了一定的理论指导。