Electrochemical behavior of K3Fe(CN)6 in water-in-oil microemulsion

Abstract

A water-in-oil (W/O) microemulsion composed of Triton X-100, n-hexanol, n-hexane and water solution with hydrochloric acid was prepared. K 3 Fe(CN) 6 was added in as a water-soluble electroactive probe, and its electrochemical behavior was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It is found that the H + concentration of the water phase has a great effect on the conductivity of the W/O microemulsion, and hence influences the electrochemical behavior of K 3 Fe(CN) 6 . When the pH value of water phase is about 7, the electrical conductivity of the W/O microemulsion is only 1.2×10 −6 S/cm, and K 3 Fe(CN) 6 almost cannot react at the glassy carbon electrode. But when the H + concentration is more than 3 mol/L, the W/O microemulsion has a good electrical conductivity and K 3 Fe(CN) 6 shows good electrochemical performance in it. The results of CV and EIS studies indicate that the electrochemical behavior of Fe(CN) 6 3− /Fe(CN) 6 4− in the W/O microemulsion is different from that in the aqueous solution. This may be due to the unique liquid structure of the W/O microemulsion and the unique mass transfer in the W/O microemulsion.

Simple and direct potentiometric determination of potassium ions in biodiesel microemulsions at a glassy carbon electrode modified with nickel(ii) hexacyanoferrate nanoparticles

“…This decrease is due to the higher difficulty of charge transporting the microemulsion to the modied electrode surface compared with charge transporting in the aqueous medium, this is a result of the microemulsion not being a continuous medium. 17 The electrochemical behavior of NiHCFNP in microemulsion in the presence of KCl was studied by CV between À0.2 and 1.0 V at a scan range of 20 to 175 mV s À1 . The peak currents were proportional to the scan rate at this range indicating the occurance of an electrochemical process controlled by adsorption, like in aqueous medium.…”

“…Considering the sample preparation for electrochemical measurements, microemulsions have been shown to be a great medium for these applications, in the case of matrices immiscible with water and supporting electrolytes. [14][15][16][17] Using the preparation of microemulsion for sample preparation, it becomes possible to directly analyse matrices, such as biodiesel, without the destruction of organic matter and the need for extraction. Mendonça et al 14 demonstrated, through the redox process of ferrocene and oleic acid, that it is possible to carry out quantitative electroanalytical determinations in microemulsions.…”

MADS-Box Family Genes in Lagerstroemia indica and Their Involvement in Flower Development

“…Early observations of its phenotypic and physiological indicators revealed that the pollen was inactive and microspore fertility was low. The anatomic study on the process of differentiation showed that the embryo sac abortion was caused by the abnormal tapetum layer during the embryo sac development of ‘Xiang Yun’ [ 22 ]. However, the underlying mechanism by which genes are responsible for its flower organ development and interactions with plant hormones remains unclear.…”