Department of Chemical & Biomolecular Engineering, University of Illinois at Urbana-Champaign, 114 Roger Adams Laboratory, MC-712, 600 S. Mathews Avenue, Urbana, Illinois 61801, USA.
Nano Lett. 2013 Jun 12;13(6):2870-4. doi: 10.1021/nl401214d. Epub 2013 May 6.
Highly uniform Pt icosahedral nanocrystals with an edge length of 8.8 nm were synthesized in nonhydrolytic systems using the hot injection-assisted GRAILS (gas reducing agent in liquid solution) method. The results show the key factors for the shape control include fast nucleation, kinetically controlled growth, and protection from oxidation by air. The effect of oxygen molecules on the Pt morphology was experimentally confirmed based on the study of shape evolution of icosahedral crystals upon exposure to oxygen gas. The Pt icosahedral catalysts obtained had an area-specific activity of 0.83 mA/cm(2) Pt, four times that of 0.20 mA/cm(2) Pt for typical Pt/C catalysts, in an oxygen reduction reaction (ORR).
采用热注射辅助 GRAILS（液体溶液中的气体还原剂）法，在非水解体系中合成了具有 8.8nm 边长的高度均匀的 Pt 二十面体纳米晶体。结果表明，形状控制的关键因素包括快速成核、动力学控制生长和防止空气氧化。基于对暴露于氧气时二十面体晶体形态演变的研究，实验证实了氧分子对 Pt 形态的影响。在氧还原反应（ORR）中，所获得的 Pt 二十面体催化剂的比表面积活性为 0.83 mA/cm(2)Pt，是典型的 Pt/C 催化剂的 0.20 mA/cm(2)Pt 的四倍。
