高性能燃料电池催化剂：三维石墨烯负载铂基纳米粒子的构筑及性能调控

Control fabrication of electrocatalyst with excellent electrocatalytic performances is crucial for commercialization of fuel cells in widespread applications. Here, a new kind of porous electrocatalyst will be achieved through supporting controllable Pt-based multimetallic nano-alloys (PtM: M= Fe, Co, Ni, Cu) by three-dimensional (3D) porous graphene using the supercritical fluid technique. The effects of supercritical fluid system’s key parameters (such as pressure, temperature, time, rate of decompression) on the particle sizes, loading and dispersion of nanoparticles in 3D graphene, and the thermodynamic and kinetic behaviors of nanoparticle nucleary and growth will be investigated. The key parameters of system for controllable fabrication of porous electrocatalyst can be obtained, and the synthesis mechanism will be understood. Relationship between the electrocatalytic performances and micro-structures of as-prepared porous electrocatalysts (such as micro-porous structure of 3D graphene, micro-component and structure, and interaction between support and nanoparticles) will be investigated in details. The electrocatalytic mechanism of synergic relationship in porous electrocatalyst will be demonstrated. Studies here will provide the fundamental research theories for the application of 3D graphene in fuel cells as advanced support, and control synthesis of electrocatalyst with low cost, high electrocatalytic activity and high durability. The research results will also promote the applications of such porous electrocatalysts in the field of new energy in the future.

高性能催化剂的可控制备对推动燃料电池大规模的实际应用具有重要作用，本项目拟利用自主搭建的超临界流体系统将铂基多元合金（PtM：M=Fe、Co、Ni、Cu）纳米粒子可控负载于三维石墨烯中形成多孔催化剂。研究超临界流体系统中关键参数（压强、温度、时间、泄压速率等）对多孔催化剂中纳米粒子的尺寸、负载量、分散状态的影响，研究不同系统参数下Pt基粒子的成核、生长的热力学和动力学行为，获得多孔催化剂的可控且稳定制备的系统参数，并揭示其合成机理。研究多孔催化剂的微观结构（包括三维石墨烯的多孔结构、多元合金粒子的微观组成和结构以及三维石墨烯和粒子间的相互作用）对催化性能的影响，并揭示其影响机理。通过本项目的研究，不仅为三维石墨烯在燃料电池催化剂载体中的应用提供理论基础，更为低成本、高催化活性、高稳定性的燃料电池催化剂的可控合成提供理论指导，从而推动此类多孔催化剂在新能源领域的实际应用。

高性能催化剂的可控制备对推动燃料电池大规模的实际应用具有重要作用，本项目利用自主搭建的超临界流体系统以及一般的热解工艺，以三维石墨烯为载体，将铂基多元合金（PtM：M=Fe、Co、Ni、Cu）纳米粒子可控负载于孔道中，得到的复合材料应用于质子交换膜燃料电池阴极催化剂。考察制备工艺条件对复合材料微观结构如尺寸、负载量、分散状态等的影响。分别在酸性和碱性条件下，研究纳米粒子负载多孔催化剂的微观结构（包括三维石墨烯的多孔结构、多元合金粒子的微观组成和结构以及三维石墨烯和粒子间的相互作用）对催化性能的影响，并揭示其影响机理。通过本项目的研究，不仅为三维石墨烯在燃料电池催化剂载体中的应用提供理论基础，更为低成本、高催化活性、高稳定性的燃料电池催化剂的可控合成提供理论指导，推动此类多孔催化剂在新能源领域的实际应用。