金属纳米簇/石墨烯复合体系的可控制备及电催化性质研究

Noble metal catalyst is currently one of the bottlenecks for commercialization of fuel cells. How to reduce the cost of the catalyst when enchancing its reactivity and stability is the demanding fundamental scientific and technical problem to be dissolved. On one hand,the performance of nanometal catalysts depends on the properties of metal nanoparticles; on the other hand, the support also plays an important role. Graphene, as a two-dimensional carbon nanomaterial with excellent properties, is highly prospected to be the perfect support to metal nanocatalyst. How to realize the synergistic effect between graphene and metal nanoparticles, however, remains a great challenge. In this project, the applicant would like to reduce metal nanoclusters in-situ utilizing three kinds of graphene support with distinct properties, i.e. graphene oxide, reduced graphene oxide and doped graphene. The catalytic performance of the metal nanocluster/graphene on oxygen reduction reaction and methanol oxidation reaction will be studied. By tailoring the size, chemical composition as well as the micro-structure of the metal nanoculsters, the influences of the synergestic effect between graphene and metal nanoculsters on the catalytic performance will be investigated thorouthly. It is hoped that combined with theoretical calculation, the influences of molecules absorption, energy transfer and synergistic effect of metal nanocluster/graphene on the catalytic performance, will be elucidated further. The applicant will explore the versatile rules to prepare metal nanocluster catalysts supported on graphene, providing research stradegies to develop practical fuel cells.

贵金属纳米催化剂是目前燃料电池商业化的主要瓶颈之一。在提高催化剂活性和稳定性的同时降低材料成本，是目前亟待解决的关键科学技术问题。纳米金属催化剂的性能，一方面取决于金属纳米粒子的性质，另一方面载体也起着关键的作用。石墨烯作为性能优异的的二维纳米碳材料，有希望成为金属纳米催化剂的理想载体；但是如何实现石墨烯与金属纳米粒子的协同效应，依然是一个巨大的挑战。本项目拟采用氧化石墨烯、还原氧化石墨烯和掺杂石墨烯为载体原位还原金属纳米簇，催化氧气还原和甲醇氧化反应，通过调控石墨烯的性质以及金属纳米簇的尺寸、化学组成和微观结构，详细研究它们之间的协同效应对催化性能的影响，提高催化剂的活性、稳定性和选择性。申请者希望结合理论计算，在微观尺度上进一步深入认识金属纳米簇/石墨烯复合体系的分子吸附、能量转移和协同效应对催化机理的影响，探索石墨烯基金属纳米簇催化剂的普适性规律，为开发实用的燃料电池提供研究思路。

本项目围绕金属、半导体纳米颗粒的结构调控，构建与石墨烯等二维纳米材料的杂化结构，通过元素组成、形貌、结构调控等详细研究围观结构与光电催化性能的内在关联。本课题开展了以金属/石墨烯二维纳米材料在氧气还原反应的应用研究，并原位制备石墨烯/二氧化钛三维纳米网络结构，显示出优异的电脱盐性能。本课题也尝试了半导体纳米材料在光催化产氢、产氧和CO2光催化还原等性能的应用研究。并进一步结合理论计算，在微观尺度上阐述了晶面原子结构、表面吸附、键能等参数对催化机理的影响。