Department of Chemistry, Sungkyunkwan University, Suwon 440-746, South Korea.
Nanoscale. 2019 Feb 7;11(6):2840-2847. doi: 10.1039/c8nr08231f.
In this work, we demonstrate how to synthesize a three-dimensional (3D) ordered PtAu nanoframe superstructure and evaluated its performance as an electrocatalyst. Compared to carbon supported platinum (Pt) nanocrystal electrocatalysts (wherein the aggregation- and carbon corrosion-induced fast degradation is a well-known drawback), the 3D PtAu nanoframe superstructure is free from aggregation and carbon corrosion. The 3D superstructure was self-assembled via drop-casting and evaporation using truncated octahedral PtAu nanoframes (TOh PtAu NFs) as building blocks that were produced by controlled wet-chemical etching of a TOh Au core whose edges and vertexes were selectively deposited with Pt atoms. Density functional theory calculations revealed that the surface alloy state of PtAu gave rise to an enhanced catalytic activity compared to pure Pt. Experimental investigations showed that such 3D superstructure electrocatalysts exhibited excellent mass transfer efficiency, higher catalytic activity and stability towards the methanol oxidation reaction (MOR) compared to a commercial Pt/C catalyst. The demonstrated 3D nanoframe superstructure shows great potential for practical catalytic application due to its high structural stability, high catalytic activity, high surface area and ease of fabrication.
在这项工作中，我们展示了如何合成三维（3D）有序 PtAu 纳米框架超结构，并评估了其作为电催化剂的性能。与碳负载的铂（Pt）纳米晶电催化剂（其中众所周知的缺点是聚集和碳腐蚀引起的快速降解）相比，3D PtAu 纳米框架超结构不会发生聚集和碳腐蚀。该 3D 超结构通过滴铸和蒸发自组装而成，使用截断八面体 PtAu 纳米框架（TOh PtAu NFs）作为构建块，TOh Au 核通过受控的湿化学蚀刻产生，其边缘和顶点选择性地沉积了 Pt 原子。密度泛函理论计算表明，PtAu 的表面合金状态导致其催化活性相对于纯 Pt 得到增强。实验研究表明，与商业 Pt/C 催化剂相比，这种 3D 超结构电催化剂在甲醇氧化反应（MOR）中表现出优异的传质效率、更高的催化活性和稳定性。由于其高结构稳定性、高催化活性、高表面积和易于制造，所展示的 3D 纳米框架超结构在实际催化应用中具有很大的潜力。
