Double complex salts (DCSs) with [M(NH3)(5)Cl](2+) (M = Rh, Ir, Co, Cr, Ru) cations and [PtBr4](2-) anions were prepared in high yields. The salts were two-phase mixtures of the anhydrous and monohydro DCSs. Anhydrous analogues containing [PdBr4](2-) anions with M = Cr or Ru were synthesized. All the compounds were characterized using a set of physicochemical methods. The crystal structure of chloropentaamminechromium(III) tetrabromopalladate(II) was solved: space group Pnma, Z = 4, a = 17.068(2) angstrom, b = 8.315(12) angstrom, c = 9.653(14) angstrom. The [M(NH3)(5)Cl][M'X-4] (M = Rh, Ir, Co, Cr, Ru; M' = Pd, Pt; X = Cl, Br) compounds were shown to be isostructural. The [M(NH3)(5)Cl][PtBr4] center dot H2O monohydrates are isostructural to the [M(NH3)(5)Cl][PdCl4] center dot H2O monohydrates (space group P2(1)/c, z = 4). The properties of the compounds were comparatively analyzed. The tendencies of the thermal stability of the complexes were elucidated. The thermolysis products of the double complex salts obtained under a helium or hydrogen atmosphere were studied.
Synthesis and electrochemical study of Pt-based nanoporous materials
作者:Jingpeng Wang、Peter Holt-Hindle、Duncan MacDonald、Dan F. Thomas、Aicheng Chen
DOI:10.1016/j.electacta.2008.02.028
日期:2008.10
surface areas of these nanoporous Pt-based alloy catalysts are increased by over 68 (Pt–Pd), 69 (Pt–Ru) and 113 (Pt–Ir) fold compared to a polycrystalline Pt electrode. All these synthesized nanoporous electrodes exhibit superb electrocatalytic performance towards electrochemical oxidation of methanol and formic acid. Among the five nanoporous Pt-based electrodes, the Pt–Ir shows the highest peak current
Microtubular Hydrogen Electrode, a Reference Electrode for Electrochemical Analyses
作者:Masayuki Kunimatsu、Huan Qiao、Tatsuhiro Okada
DOI:10.1149/1.1874732
日期:——
specific feature of the tubular hydrogen electrode is that it is so small that it can fit in microanalytical or electrochemical cell systems. The tubular hydrogen electrode can also work as both a counter electrode and a nonpolarizable reference electrode because of the very large specific surface area of the platinum particles deposited inside. This makes these tubular hydrogen electrodes usable in two-electrode
Arrays of Ru, Pt, and PtRu one dimensional 1D nanowires NWs and nanotubes NTs were prepared by electrodeposition through the porous structure of an anodic aluminum oxide AAO membrane. In each case, micrometer-long NW and NT were formed with an outer diameter of ca. 200 nm, close to the interior diameter of the porous AAO membrane. Arrays of NW and NT can be formed by varying the metallic salt concentration
通过阳极氧化铝 AAO 膜的多孔结构,通过电沉积制备 Ru、Pt 和 PtRu 一维一维纳米线 NW 和纳米管 NT 的阵列。在每种情况下,微米长的 NW 和 NT 形成的外径约为 200 nm,接近多孔 AAO 膜的内径。NW 和 NT 阵列可以通过改变金属盐浓度、施加的电位和电解质的电导率来形成。使用电化学石英晶体微天平在各种沉积条件下测量 Ru 和 Pt 沉积速率。基于观察到的沉积速率和文献中发现的模型讨论了负责形成 Ru 和 Pt NW 和 NT 的机制。最后,
Sputtered Pt–Ru Alloys as Catalysts for Highly Concentrated Methanol Oxidation
作者:Xirong Jiang、Turgut M. Gür、Friedrich B. Prinz、Stacey F. Bent
DOI:10.1149/1.3273081
日期:——
further shows that the cosputtered films are highlyalloyed. The electrochemical behavior of the sputtered films has been evaluated for methanoloxidation using cyclic voltammetry and chronoamperometry in the H 2 SO 4 /CH 3 OH electrolyte at room temperature. The results indicate that Pt 0.53 Ru 0.47 is the optimal alloy composition for highlyconcentrated 16.6 M CH 3 OH, which corresponds to the stoichiometric
对于采用 1:1 化学计量甲醇-水重整混合物的直接甲醇燃料电池 (DMFC) 中可能的催化阳极,我们研究了广泛组成范围内的溅射 Pt-Ru 催化剂。由扫描电子显微镜研究确定的催化剂薄膜的表面形态是粗糙和纳米多孔的,并且取决于组成。通过X射线衍射分析证实薄膜的结构为多晶,这进一步表明共溅射薄膜是高度合金化的。使用循环伏安法和计时电流法在室温下在 H 2 SO 4 /CH 3 OH 电解质中评估了溅射薄膜的电化学行为,用于甲醇氧化。结果表明,Pt 0.53 Ru 0.47 是高浓度 16.6 M CH 3 OH 的最佳合金成分,这对应于将用于旨在减轻甲醇交叉的下一代 DMFC 中的化学计量燃料。长时间计时电流法测量表明,溅射 Pt-Ru 催化剂在初始衰减后保持稳定的性能。
Comparison of High-Throughput Electrochemical Methods for Testing Direct Methanol Fuel Cell Anode Electrocatalysts
作者:Benny C. Chan、Renxuan Liu、Krishnakumar Jambunathan、Hong Zhang、Guoying Chen、Thomas E. Mallouk、Eugene S. Smotkin
DOI:10.1149/1.1857772
日期:——
fluorescence detection in aqueous methanol solutions containing a fluorescent acid-base indicator, steady-state voltammetry in a 25 electrode array fuelcell with a large common counter electrode, and steadystate voltammetry in a conventional directmethanolfuelcell. The fluorescence detection method, which is a high-throughput technique developed for large arrays of electrocatalysts, can distinguish active