Branch Jack A, Cook David A, Bartlett Philip N
School of Chemistry, University of Southampton, Southampton, UKSO171BJ.
Phys Chem Chem Phys. 2015 Jan 7;17(1):261-7. doi: 10.1039/c4cp04545a.
Detailed analysis of the voltammetry of decamethylferrocene at micro and macrodisc electrodes has been carried out in scCO2/MeCN (15 wt%), 20 mM [NBu(n)4][BF4] and 309 K and 17.5 MPa. A passivating film needs to be removed from platinum electrodes before stable, reproducible voltammetry can be obtained. At low concentrations (0.22 mM) reversible 1e(-) behaviour is observed. Significant effects from natural convection are also present and it is demonstrated that fitting a baffle to the electrode dampens this effect. Limiting currents at microdisc electrodes at concentrations ranging from 0.22 to 11 mM and radii of 10 to 25 μm all obey the microdisc equation. The diffusion coefficient is calculated to be 4.06 × 10(-5) cm(2) s(-1) in scCO2/MeCN (15 wt%) with 20 mM [NBu(n)4][BF4] and 309 K at 17.5 MPa. The solubility of decamethylferrocene is in excess of 11 mM for these conditions.
在309 K和17.5 MPa条件下，于超临界二氧化碳/乙腈（15 wt%）、20 mM四正丁基铵四氟硼酸盐[ NBu(n)4][BF4]体系中，对十甲基二茂铁在微盘和宏盘电极上的伏安法进行了详细分析。在获得稳定、可重复的伏安法之前，需要从铂电极上去除钝化膜。在低浓度（0.22 mM）下观察到可逆的单电子行为。自然对流也有显著影响，并且证明在电极上安装挡板可减弱这种影响。在浓度范围为0.22至11 mM且半径为10至25 μm的微盘电极上的极限电流均符合微盘方程。在309 K和17.5 MPa条件下，于含有20 mM [NBu(n)4][BF4]的超临界二氧化碳/乙腈（15 wt%）体系中，计算得出十甲基二茂铁的扩散系数为4.06×10⁻⁵ cm² s⁻¹。在这些条件下，十甲基二茂铁的溶解度超过11 mM。
