A droplet of aqueous solution containing a certain molar ratio of redox couple is first attached onto a platinum electrode surface, then the resulting drop electrode is immersed into the organic solution containing ve...A droplet of aqueous solution containing a certain molar ratio of redox couple is first attached onto a platinum electrode surface, then the resulting drop electrode is immersed into the organic solution containing very hydrophobic electrolyte. Combined with reference and counter electrodes, a classical three-electrode system has been constructed. Ion transfer (IT) and electron transfer (ET) are investigated systematically using three-electrode voltammetry. Potassium ion transfer and electron transfer between potassium ferricyanide in the aqueous phase and ferrocene in nitrobenzene are observed with potassium ferricyanide/potassium ferrocyanide as the redox couple. Meanwhile, the transfer reactions of lithium, sodium, potassium, proton and ammonium ions are obtained with ferric sulfate/ferrous sulfate as the redox couple. The formal transfer potentials and the standard Gibbs transfer energy of these ions are evaluated and consistent with the results obtained by a four-electrode system and other methods.展开更多
A new kind of nonionic surfactant ionophore is introduced to facilitate metal ion transfer across a liquid/liquid interface. The transfer of Na+ facilitated by emulsifier OP across the water/nitrobenzene interface has...A new kind of nonionic surfactant ionophore is introduced to facilitate metal ion transfer across a liquid/liquid interface. The transfer of Na+ facilitated by emulsifier OP across the water/nitrobenzene interface has been studied by semi-differential cyclic voltammetry, and a new method for the determination of emulsifier OP was established. The proposed method is simple, easy and effective.展开更多
The phase transfer mechanism of 18-molybdophosphate anion at the water/nitrobenzene interfaca has been investigated by chronopotentiometry with cyclic linear current-scanning (CLC) and cyclic voltammetry (CV). The tra...The phase transfer mechanism of 18-molybdophosphate anion at the water/nitrobenzene interfaca has been investigated by chronopotentiometry with cyclic linear current-scanning (CLC) and cyclic voltammetry (CV). The transfer species is 18-molybdophosphtae anion with a charge number of-4, H_2[P_2Mo_(18)O_(62)]^(4-). The transfer process is controlled by diffusion at a slow polarization rate and considerably influenced by pH of the aqueous phase. The stable forms and pH range of the heteropoly anion in the aqueous solution can be directly confirmed through voltammetric behavior. The theoretical analysis of the relationship between the transfer potential and solution pH is identical to the experimental results. The linear concentration relationship with the transfer peak current is suggested to be used in the determination of heteropoly acids(salts).展开更多
基金This work was supported by the Chinese Academy of Sciences (CAS), the National Natural Science Foundation of China (Grant No. 29825111) the State Key Laboratory of Electroanalytical Chemistry of the CAS.
文摘A droplet of aqueous solution containing a certain molar ratio of redox couple is first attached onto a platinum electrode surface, then the resulting drop electrode is immersed into the organic solution containing very hydrophobic electrolyte. Combined with reference and counter electrodes, a classical three-electrode system has been constructed. Ion transfer (IT) and electron transfer (ET) are investigated systematically using three-electrode voltammetry. Potassium ion transfer and electron transfer between potassium ferricyanide in the aqueous phase and ferrocene in nitrobenzene are observed with potassium ferricyanide/potassium ferrocyanide as the redox couple. Meanwhile, the transfer reactions of lithium, sodium, potassium, proton and ammonium ions are obtained with ferric sulfate/ferrous sulfate as the redox couple. The formal transfer potentials and the standard Gibbs transfer energy of these ions are evaluated and consistent with the results obtained by a four-electrode system and other methods.
文摘A new kind of nonionic surfactant ionophore is introduced to facilitate metal ion transfer across a liquid/liquid interface. The transfer of Na+ facilitated by emulsifier OP across the water/nitrobenzene interface has been studied by semi-differential cyclic voltammetry, and a new method for the determination of emulsifier OP was established. The proposed method is simple, easy and effective.
文摘The phase transfer mechanism of 18-molybdophosphate anion at the water/nitrobenzene interfaca has been investigated by chronopotentiometry with cyclic linear current-scanning (CLC) and cyclic voltammetry (CV). The transfer species is 18-molybdophosphtae anion with a charge number of-4, H_2[P_2Mo_(18)O_(62)]^(4-). The transfer process is controlled by diffusion at a slow polarization rate and considerably influenced by pH of the aqueous phase. The stable forms and pH range of the heteropoly anion in the aqueous solution can be directly confirmed through voltammetric behavior. The theoretical analysis of the relationship between the transfer potential and solution pH is identical to the experimental results. The linear concentration relationship with the transfer peak current is suggested to be used in the determination of heteropoly acids(salts).
