Kinetic studies on the electron transfer(ET) reaction of [Co(NH3)5(ImH)]3+/[Fe(CN)6]4- and trans-[Co(NH3)(en)2(ImH)]3+/[Fe(CN)6]4- have been carried out at various temperatures. The results indicated that these two ET...Kinetic studies on the electron transfer(ET) reaction of [Co(NH3)5(ImH)]3+/[Fe(CN)6]4- and trans-[Co(NH3)(en)2(ImH)]3+/[Fe(CN)6]4- have been carried out at various temperatures. The results indicated that these two ET reactions followed the outersphere mechanism. At 25℃,I=0.50mol’L-1, the ion pair formation constants Qip ofthe prectirsor complexes in the ET reactions are 2.6×102 and 4.9 × 1O2mol’L-1 ,and theelectron transfer rate constants kct are 2.1 ×10-4 and 5.2 ×10-5s-1 respectively. The activation enthalpy and the activation entropy of these two processes are 1.2×1O2,0.8 ×102kJ ’mol -1 and 5. 1×102, 3.6 ×102J·mol-1 ·K-1 respectively.展开更多
The influence of Na2 SO4 on the formation of ZnO whiskers was investigated in this paper. ZnO whiskers with aspect ratios of up to 50 were synthesized by dissolving ε-Zn（OH）2 precursor in NaOH/Na2SO4 solution at ro...The influence of Na2 SO4 on the formation of ZnO whiskers was investigated in this paper. ZnO whiskers with aspect ratios of up to 50 were synthesized by dissolving ε-Zn（OH）2 precursor in NaOH/Na2SO4 solution at room temperature, followed by aging of the resulting solution at 140 ℃ for 6 h. Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy analyses revealed that SO4^2- ions were primarily adsorbed on the （1 00） plane of the ZnO whiskers via an outer-sphere com- plex configuration （O-H……O）, thereby promoting the one-dimensional growth of ZnO whiskers along the c-axis.展开更多
The oxidation of Na4Fe(CN)6 complex by S2O8 2- anion was found to follow an outer-sphere electron transfer mechanism. We firstly carried out the reaction at pH=1. The specific rate constants of the reaction...The oxidation of Na4Fe(CN)6 complex by S2O8 2- anion was found to follow an outer-sphere electron transfer mechanism. We firstly carried out the reaction at pH=1. The specific rate constants of the reaction, kox, are (8.1± 0.07)×10-2 and (4.3±0.1)×10-2 mol-1?L?s-1 at μ=1.0 mol?L-1 NaClO4, T=298 K for pH=1 (0.1 mol?L-1 HClO4) and 8, respectively. The activation parameters, obtained by measuring the rate constants of oxidation 283—303 K, were ?H≠=(69.0±5.6) kJ?mol-1, ?S≠=(-0.34±0.041)×102 J?mol-1?K-1 at pH=1 and ?H≠= (41.3±5.5) kJ?mol-1, ?S≠=(-1.27±0.33)×102 J?mol-1?K-1 at pH=8, respectively. The cyclic voltammetry of Fe(CN)36 -/4- shows that the oxidation is a one-electron reversible redox process with E1/2 values of 0.55 and 0.46 V vs. normal hydrogen electrode at μ=1.0 mol?L-1 LiClO4, for pH=1 and pH=8 (Tris), respectively. The kinetic results were discussed on the basis of Marcus theory.展开更多
文摘Kinetic studies on the electron transfer(ET) reaction of [Co(NH3)5(ImH)]3+/[Fe(CN)6]4- and trans-[Co(NH3)(en)2(ImH)]3+/[Fe(CN)6]4- have been carried out at various temperatures. The results indicated that these two ET reactions followed the outersphere mechanism. At 25℃,I=0.50mol’L-1, the ion pair formation constants Qip ofthe prectirsor complexes in the ET reactions are 2.6×102 and 4.9 × 1O2mol’L-1 ,and theelectron transfer rate constants kct are 2.1 ×10-4 and 5.2 ×10-5s-1 respectively. The activation enthalpy and the activation entropy of these two processes are 1.2×1O2,0.8 ×102kJ ’mol -1 and 5. 1×102, 3.6 ×102J·mol-1 ·K-1 respectively.
基金supported by the National Natural Science Foundation of China(Nos.51174125,51234003,and 51374138)
文摘The influence of Na2 SO4 on the formation of ZnO whiskers was investigated in this paper. ZnO whiskers with aspect ratios of up to 50 were synthesized by dissolving ε-Zn（OH）2 precursor in NaOH/Na2SO4 solution at room temperature, followed by aging of the resulting solution at 140 ℃ for 6 h. Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy analyses revealed that SO4^2- ions were primarily adsorbed on the （1 00） plane of the ZnO whiskers via an outer-sphere com- plex configuration （O-H……O）, thereby promoting the one-dimensional growth of ZnO whiskers along the c-axis.
基金Project supported by the National Natural Science Foundation of China (No. 20171010).
文摘The oxidation of Na4Fe(CN)6 complex by S2O8 2- anion was found to follow an outer-sphere electron transfer mechanism. We firstly carried out the reaction at pH=1. The specific rate constants of the reaction, kox, are (8.1± 0.07)×10-2 and (4.3±0.1)×10-2 mol-1?L?s-1 at μ=1.0 mol?L-1 NaClO4, T=298 K for pH=1 (0.1 mol?L-1 HClO4) and 8, respectively. The activation parameters, obtained by measuring the rate constants of oxidation 283—303 K, were ?H≠=(69.0±5.6) kJ?mol-1, ?S≠=(-0.34±0.041)×102 J?mol-1?K-1 at pH=1 and ?H≠= (41.3±5.5) kJ?mol-1, ?S≠=(-1.27±0.33)×102 J?mol-1?K-1 at pH=8, respectively. The cyclic voltammetry of Fe(CN)36 -/4- shows that the oxidation is a one-electron reversible redox process with E1/2 values of 0.55 and 0.46 V vs. normal hydrogen electrode at μ=1.0 mol?L-1 LiClO4, for pH=1 and pH=8 (Tris), respectively. The kinetic results were discussed on the basis of Marcus theory.
