Block copolymer reduces, protects and mediates oriented growth into nano/submicron branched platinum
Block copolymer reduces, protects and mediates oriented growth into nano/submicron branched platinum
复制标题
嵌段共聚物减少、保护和介导纳米/亚微米支化铂的定向生长
DOI：
10.1039/c2jm31542d
复制
发表时间：
2012-01-01
影响因子：
--
通讯作者：
Li, Fan
中科院分区：
文献类型：
--
作者：
Wang, Yan;Zhang, Lijuan;Li, Fan
以聚环氧乙烷-聚环氧丙烷-聚环氧乙烷（Pluronic F127，PEO 100 PPO 65 PEO 100）为原料，采用自还原回流法合成了新型纳米/亚微米支化铂（B-Pt）。所制备的B-Pt阵列在亚微米级时尺寸较大，但在纳米级时呈现出许多相互连接的分形树枝状结构，每个分支的直径都在纳米级。高分辨透射电子显微镜（HRTEM）显示B-Pt通常暴露于（111）面，具有高密度的棱角，广泛的晶格畸变，台阶和悬浮原子，这些都有利于电催化。电化学测试，比较动力学电流，进一步证实了B-Pt的氧还原反应（ORR）活性优于现有的商业Pt黑和Pt/C催化剂。该共聚物同时具有还原、保护和定向作用，并详细阐述了B-Pt的生长机理。
New nano/submicron branched platinum (B-Pt) was readily synthesized by auto-reduction reflux of H2PtCl6 solution mixed with poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (Pluronic F127, PEO100PPO65PEO100). The as-prepared B-Pt shows many interconnected fractal twigs with the diameter of each branch at nano-level though the whole B-Pt array is relatively large at submicron size. High resolution transmission electron microscopy (HRTEM) shows that the B-Pt generally exposed (111) planes and possesses a high density of edges and corners, widespread lattice distortions, step and suspension atoms, which are all beneficial for electrocatalysis. Electrochemical tests, comparing the kinetic current, further confirmed that the oxygen reduction reaction (ORR) activity of the B-Pt was better than that of current commercial Pt black and Pt/C catalysts. The copolymer serves as reducing, protecting and orienting agent at the same time and the growth mechanism of B-Pt is described in detail.