Rodríguez Paramaconi, Solla-Gullón José, Vidal-Iglesias Francisco J, Herrero Enrique, Aldaz Antonio, Feliu Juan M
Departamento de Química Física and Instituto de Electroquímica, Universidad de Alicante, Apdo. 99, E-03080 Alicante, Spain.
Anal Chem. 2005 Aug 15;77(16):5317-23. doi: 10.1021/ac050347q.
Irreversible adsorbed bismuth can be used to determine the fraction of (111) domains on a given platinum sample. On Pt(111) electrodes, the surface redox process of adsorbed bismuth takes place at 0.63 V in a well-defined peak. The behavior of this redox process on the Pt(111) vicinal surfaces indicates that the bismuth atoms involved in the redox process are only those deposited on the (111) terrace sites and that the charge under the peak at 0.63 V is directly proportional to the number of sites on (111) ordered domains (terraces). The good linear relationship obtained between the charge for the bismuth redox process and the number of (111) terrace sites on the vicinal surfaces allows construction of a calibration curve. This calibration curve has been used to directly estimate the amount of (111) ordered domain terrace sites on polycrystalline platinum samples with different surface ordered domains. The results agree with what we would expect from our knowledge of these surfaces.
不可逆吸附的铋可用于确定给定铂样品上(111)畴的比例。在Pt(111)电极上，吸附铋的表面氧化还原过程在0.63 V处呈现出一个明确的峰。该氧化还原过程在Pt(111)邻位表面上的行为表明，参与氧化还原过程的铋原子仅为沉积在(111)台阶位点上的那些，并且0.63 V处峰下的电荷与(111)有序畴（台阶）上的位点数量成正比。在铋氧化还原过程的电荷与邻位表面上(111)台阶位点数量之间获得的良好线性关系使得能够构建校准曲线。该校准曲线已用于直接估计具有不同表面有序畴的多晶铂样品上(111)有序畴台阶位点的数量。结果与我们对这些表面的了解所预期的一致。
