DOI: 10.5061/dryad.2z34tmpsb
title: Data from: Interfacial tension hysteresis of eutectic gallium-indium

description: When in a pristine state, gallium and its alloys have the largest
 interfacial tensions of any liquid at room temperature. Nonetheless,
 applying as little as 0.8 V of electric potential across eutectic gallium
 indium (EGaIn) placed within aqueous NaOH (or other electrolyte) solution
 will cause the metal to behave as if its interfacial tension is near zero.
 The mechanism behind this phenomenon has remained poorly understood
 because NaOH dissolves the oxide species, making it difficult to directly
 measure the concentration, thickness, or chemical composition of the film
 that forms at the interface. In addition, the oxide layers formed are
 atomically-thin. Here, we present a suite of techniques which allow us to
 simultaneously measure both electrical and interfacial properties as a
 function of applied electric potential, allowing for new insights into the
 mechanisms which cause the dramatic liquid metal, oxidation, and
 interfacial tension decrease in interfacial tension.  A key
 discovery from this work is that the interfacial tension displays
 hysteresis while lowering the applied potential. We combine these
 observations with electrochemical impedance spectroscopy to evaluate how
 these changes in interfacial tension arise from chemical, electrical, and
 mechanical changes on the interface, and close with ideas for how to build
 a free energy model to predict these changes from first principles.
description: Data was collected using 3 techiniques: imaging of sessile drops
 (image processing, edge-detection), cyclic voltammetry, and
 electrochemical impedance spectroscopy.
description: # Data from: Interfacial Tension Hysteresis of Eutectic Gallium-Indium
 These files are sufficient
 to recreate the plots in the paper, including the raw data from which they
 are derived. ## figures.tgz This archives contains the following files: *
 **ImageAnalysisData:** The analysis results of the 6 videos
 220414_ag_1M_010mVps_VTP (*).avi, split into 5 types of text files
 consisting of a single column of data each. Files named by
 videoNumber_Date_experimentLetterCode_MolarityOfNaOH_VoltageSweepRate_TypeOfExperiment (video number for experiment)_avi_data type.txt for the nine types of data: * File 1: Area_1 (surface area) * File 2: Area_2 (surface area) * File 3: EdgeL (Left Edge Location in px) * File 4: EdgeR (Right Edge Location in px) * File 5: Height (height of droplet in px) * File 6: midZ (Center height location of droplet in px) * File 7: topZ (Top of droplet location in px) * File 8: xy-radius (Radius of curvature of the side of the droplet in px) * File 9: z-radius (Radius of curvature of the top of the droplet in px) * **Fig2+Fig3/Fig_2_and_3_IFT_J_vs_V_Data.xlsx** * Column 1: applied voltage to the EGaIn droplet * Column 2: Measured current density through the EGaIn droplet * Column 3: Calculated surface tension of the EGaIn droplet * **Fig4/Fig_4_EIS_Avg_Data.xlsx:** These datasets are split into four groups, Re(Impedance), STD of Re(Impedance), Im(Impedance), STD of Im(Impedance). Columns are separated by DC Bias Voltage where: * Column 1: 0.00 V bias * Column 2: 0.05 V bias * Column 3: 0.10 V bias * Column 4: 0.15 V bias * Column 5: 0.20 V bias * Column 6: 0.25 V bias * Column 7: 0.30 V bias * Column 8: 0.40 V bias * Column 9: 0.50 V bias * **Fig5/Fig_5_IFT_J_vs_V_Data.xlsx:** Data is grouped by maximum Voltage applied to the droplet, with three columns per group: * Column 1: applied voltage to the EGaIn droplet * Column 2: Measured current density through the EGaIn droplet * Column 3: Calculated surface tension of the EGaIn droplet * **Fig8: Circuit_parameters.xlsx:** The file contains the resistance and capacitance parameters used to model the Impedance data. Data is grouped by H2L (for high to low frequncy sweep) and L2H (for low to high frequency sweep) * *Resistances* * Column 1: E/ V vs. OCP * Column 2: Rsol /Ohm (solution resistance) * Column 3: Rsol Dev ( Std dev for Rsol) * Column 4: Rox/Ohm (Oxide resistance) * Column 5: Rox Dev (Std dev Rox) * Column 6: Rc1/Ohm (charge transfer resistance Rct1 element) * Column 7: Rc1 Dev (Std dev Rct1) * Column 8: Rct2/Ohm (charge transfer resistance Rct2 element) * Column 9: Rct2 Dev (Std dev Rct2) * *Capacitance* * Column 1: E/ V vs. OCP * Column 2: C Oxide μF/cm2 (capacitance of oxide) * Column 3: C Oxide Dev (td dev for C oxide) * Column 4: C Pseudo μF/cm2 (Pseudocapacitance) * Column 5: C Pseudo Dev (Std dev for C Pseudo) * **FigS3/H2L_CF and FigS3/L2H_CF:** Files are named as H2L_CF follwed by the DC Bias Voltage (for High to low frequency sweep) and L2H_CF followed by the DC Bias Voltage (for low to high frequency sweep). All .xlxs files contain the following columns: * Column 1: freq (frequency) * Column 2: Zrdata (impedance) * Column 3: Zjdata (impedance) * Column 4: Zrmodel (Circuit model impedance) * Column 5: Zjmodel (Circuit model impedance) * Column 6: SigmaZrconf (std dev Zrmodel) * Column 7: SigmaZjconf (std dev Zjmodel) * **Figs4/H2L_KK and Figs4/L2H_KK:** Files are named as H2L_KK follwed by the DC Bias Voltage (for High to low frequency sweep) and L2H_KK followed by the DC Bias Voltage (for low to high frequency sweep). All .xlxs files contain the following columns: * Column 1: freq (frequency) * Column 2: Zrdata (impedance) * Column 3: Zjdata (impedance) * Column 4: Zrmodel (KK model) * Column 5: Zjmodel (KK model) * Column 6: Real conf. interv. (std dev Zrmodel) * Column 7: Imag conf. interv. (std dev Zjmodel) ## full-video.tgz There are six videos in this archive, numbered 1 through 6, which together contain the full dynamics of a droplet becoming oxidized up to the maximum voltage, and then returning to open circuit potential. This covers all 6 voltage sweeps presented in Figure 5, from which the data above was derived.