Measurement Of Interfacial Tension Electrochemistry On A Mercury Drop Electrode And A New Approach Of In-cell IR Compensation

Two subjects, in-situ measurement of electrochemical interfacial tension and in-cell iR_u compensation, have been investigated in detailed.The first part of this dissertation includes four chapters. The theory and technology of interfacial tension measuring was reviewed in Chapter 1. In Chapter 2, a setup for the measurement of interfacial tension on a mercury drop electrode (MDE) sitting on the bottom of an electrochemical was designed, and characterized. In Chapter 3 and 4, series investigations on three chemical systems were studied, data were treated for obtaining thermodynamic parameters of the adsorption, and analyzing the mechanism of molecular adsorption, orientation and electrochemical reactions. In the second part, the technology of compensating the solution's resistance was reviewed in Chapter 5, then an in-cell compensating technique was developed by adding a grounded auxiliary working electrode (AWE) to electrochemical cell, the experimental verification and investigation of factors influenced the compensation were studied. Following results were obtained:By combining a home-made interfacial tension electrode, electrochemical cell and an electrochemical working station, in-situ and continuous interfacial tension curves at MDE/solution interface was obtained simultaneously with voltammetric curves. The measurement was well repeatable. A series of factors including the mass of mercury, the potential scan rate, the initial potential, the oxygen containmination in the solution were investigated for influencing the measurements. Studies found that the electrochemical polarize modes such as CV, LSV, NPV and I-t could be applied to the measurement, DPV and SWV techniques could not. The electrocatalytic reduction of Yb(III)-NO₂^- system was characterized by this method, demonstrating wide applicability.The behavior of TDMBA(Tetradecyldimethylbenzylammonium chloride) adsorbing on mercury electrode was studied. The in-situ interfacial tension curve differentiated well the monolayer and bilayer adsorption processes. The interfacial tension and film pressure changing with potentials at different TDMBA...