电化学合成铂基介孔纳米薄膜的新原理和新方法及其电催化性能调控

Mesostructured platinum-based nano-thinfilms (MPNTF) with three-dimensional porous metallic frameworks, high specific surface area and excellent permeability are superior low-platinum catalysts. Currently, only lyotropic liquid crystal (LLC) templated electrochemical approaches are available for synthesis of MPNTF. These demonstrated syntheses are not easy to be performed and the necessary LLC template reagents are very expensive, making the LLC-templated electrochemical synthesis very difficult to be scaled up. Addressing these bottlenecks and challenges, new principles and novel methods for electrochemical synthesis of MPNTF will be developed in this proposed project. The self-assemblies of the block copolymer micelles formed at the solid-liquid interfaces will be originally used as an soft template to direct the electrochemical formation of MPNTF. By innovatively introducing of expansion concept and dual template concept, respectively, the porous structure of the mesostructured films will be created in a controllable manner. Based on the newly developed porous-controllable electrochemical synthesis and electrocatalytic investigations, the nanopore interface effect and coupling effect at three-dimensional multi-scale will be revealed, which will be used for directing the rational design of the pore structure of mesoporous thin films to optimize their catalytic properties. Moreover, as-developed synthetic methods will be explored to fabricate mesostructured platinum-based chip electrodes in both structure and arrangement controllable manner for fuel cell applications. This project will greatly contribute to the large-scale synthesis and application of mesostructured platinum-based thin films, and will afford key technologies for the controllable design and fabrication of fuel cell chip electrodes using mesostructured platinum-based films.

铂基介孔纳米薄膜具有三维多孔金属框架、高比表面积和良好的渗透性，是优异的低铂催化剂，目前仅能通过基于溶致液晶模板的电化学合成方法制备。现有的电化学合成方法操控难度较大，且溶致液晶模板试剂价格极其昂贵，因而难以用于扩大合成。本项目针对这一瓶颈与难题，将建立电化学合成铂基介孔纳米薄膜的新原理和新方法。原创性地利用嵌段共聚物胶束在固液界面自组装形成软模板，采用电化学沉积法制备铂基介孔纳米薄膜；创新性地利用膨胀理念、双模板合成理念对介孔薄膜的孔结构进行调控和可控生长；揭示三维多尺度下纳米孔结构单元之间的界面效应和耦合效应，对介孔薄膜的孔结构进行优化设计和催化性能调控；利用建立的合成新原理和新方法，结构和排列方式可控地制备微型燃料电池用铂基介孔纳米薄膜芯片电极。本项目研究可解决铂基介孔纳米薄膜难以扩大合成和应用这一迫切需要解决的关键问题，并为铂基介孔纳米薄膜芯片电极的可控设计和制备提供关键技术。

提高贵金属铂催化剂的利用效率和催化活性是科学研究的重要问题之一。形状和成分可控地制备铂基纳米材料是获得高效低铂催化剂的有效途径。铂基介孔纳米薄膜具有高的比表面积是优异的低铂催化剂。溶致液晶模板法可有效地制备铂基介孔纳米薄膜，但该方法操作复杂而且模板试剂价格非常昂贵。建立简便制备铂基介孔纳米薄膜的新方法对其广泛应用至关重要。本项目建立了制备铂基介孔纳米薄膜的新原理和新方法，实现了对铂基介孔成份（铂、铂基双金属和铂基三金属）和孔结构的调控。系统地研究了所制备的铂基介孔纳米薄膜对燃料电池阳极反应（甲醇氧化学反应）和阴极反应（氧还原反应）的电催化性能。阐明了铂基介孔纳米薄膜的形状、结构和成分与其电催化性能之间的构效关系，获得了对其电催化性能进行调控的关键技术，制备了一系列高效的铂基介孔纳米薄膜电催化剂。相关研究成果在电催化和燃料电池领域具有一定的科学价值和应用前景。