Frequently Asked Questions

Our Reference Electrode (RE) is basically an Ag/AgCl reference electrode and it can be used for electrochemical measurements (such as Corrosion potential monitoring, Potentiodynamic polarizations, Potentiostatic polarizations, Galvanostatic polarizations, Electrochemical impedance spectroscopy (EIS), etc.) in a temperature range of 20°C to 800°C. In this temperature range (20°C to 800°C), the reference electrode can be directly immersed in the test electrolyte providing that the test electrolyte has an ionic conductivity sufficient to conduct the electrochemical measurements. 

This reference electrode can also do electrochemical measurements at temperatures lower than 20°C, (20°C to -10°C), providing that: 1) the reference electrode is immersed in saturated aqueous solution of potassium chloride (KCl) and connected to the test electrolyte through a salt bridge (a half-cell for the reference electrode), 2) the test electrolyte has an ionic conductivity sufficient to conduct the electrochemical measurements.  

Our Reference Electrode (RE) is basically an Ag/AgCl reference electrode and it can be used for electrochemical measurements (such as Corrosion potential monitoring, Potentiodynamic polarizations, Potentiostatic polarizations, Galvanostatic polarizations, Electrochemical impedance spectroscopy (EIS), etc.) in a temperature range of 20°C to 400°C. In this temperature range (20°C to 400°C), the reference electrode can be directly immersed in the test electrolyte providing that the test electrolyte has an ionic conductivity sufficient to conduct the electrochemical measurements. 

This reference electrode can also do electrochemical measurements at temperatures lower than 20°C, (20°C to -10°C), providing that: 1) the reference electrode is immersed in saturated aqueous solution of potassium chloride (KCl) and connected to the test electrolyte through a salt bridge (a half-cell for the reference electrode), 2) the test electrolyte has an ionic conductivity sufficient to conduct the electrochemical measurements.  

The main differences are the outer diameter and the seal (taper) added in the Caltrode T model.What is the difference between Caltrode +400 model and Caltrode +800 model?The difference between these two models is the temperature range.

Our Reference Electrode is Ag/AgCl electrode that measures or controls the electrochemical potential of the sample under test. So, the output data will depend on the test type. If it is Corrosion Potential Test, the output data will be Potential (Volts) versus Time (sec or min, or h or days, etc). If the test is Potentiodynamic Polarization, the output data will be Potential (Volts) versus Current (Amperes), etc. 

Our reference electrodes'  tips are made by sealing a solid Zirconia rod with the quartz in such a way to give a Nano-path for the ionic conduction. Therefore, the Zirconia rod and the quartz combination can be considered a fritted tip but with extremely narrow pores. 

Yes, we can customize the chemicals inside the electrode based on the client’s need.

Our electrode is simply an Ag/AgCl reference electrode. Its principle is the same as the well known aqueous based  Ag/AgCl reference electrode. However, we do not use any aqueous media in our electrode because it is designed to work at high temperatures up to 800℃. We use high purity chemicals for these electrodes and we obtain them from well known USA chemical companies. 

Our electrode is Ag/AgCl reference electrode. Its potential vs SCE in sat. KCl at RT was -57mV (very close to the theoretical value). Therefore, its potential vs SHE is about 200mV at RT. At high temperatures, we tested our electrode against a Reversible Oxygen Electrode (ROE) and a Reversible Hydrogen Electrode (RHE) at temperatures up to 400℃ in a molten salt and it showed no apparent dependence on temperature change and showed about 240mV (±10mV) vs RHE and -800 mV (±10mV) vs ROE. 

We recommend our Caltrode Salt Blend (NaCl-KCl-ZnCl2 ). 

The relation is almost linear. The chemicals inside the electrode are solids. Therefore, the chloride ion activity is always maintained at 1. This electrode has a unique design that allows the ionic conduction between inside and outside the electrode and maintains its reversible potential if the chemicals inside it are not fully consumed. 

The reference electrode housing is made of Quartz and its tip is made of Quartz and a ceramic rod. This tip is uniquely designed to provide ionic connection between inside the electrode and the test electrolyte. Therefore, any material mounted in the reference electrode body must be compatible taking into account thermal expansion coefficients.

Fused quartz or fused silica is known to be resistant to any attack from chemicals except the hydrofluoric acid (HF), this material has excellent thermal shock resistance and is chemically inert to most elements and compounds, including virtually all acids, regardless of concentration, except hydrofluoric acid, which is very reactive even in fairly low concentrations.

You can download the users guide available in our website. We recommend reading the user guide before use. It is critically important to avoid any thermal shock for the electrode on insertion or taking it out of the test electrolyte. It is also important to keep the electrode in a clean area after use.  

No drift can be observed if the electrode still has chemicals inside. 

Main and most important test is the electrode impedance. Acceptable impedance widely varies and depends on the user. 

For the chemicals inside electrode, to the moment we only provide sealed electrodes, and thus it is not possible to add chemicals to it when the chemicals inside are fully consumed. 

It is for Electrode Impedance measured in a molten salt (70 wt% ZnCl2+20 wt% KCl+10 wt% NaCl) at 400C after 1h, 2h and 3h immersion times.

The impedance decreases with time. Such impedance values (less than 10 K Ohms) are acceptable by many customers.The left Y-axis is the Impedance measured versus the Frequency (the X-axis). The Right Y-axis is the Phase Angle measured versus the Frequency (the X-Axis). The Phase Angle is almost Zero which is perfect for our electrode.

We recommend that one electrode should be used for only one testing medium. If one has different testing mediums, a different electrode should be used for each medium. The HT RE should not be used in both aqueous and non-aqueous mediums. If an electrode is used in an aqueous medium, it should never be used in a non-aqueous medium, and vice versa.

To validate the HT RE it must be done with a NEW (NOT contaminated) commercial Ag/AgCl, immerse our electrode and the new commercial Ag/AgCl in Saturated KCl solution for at least one hour and see the reading. At least 5 cm of our electrode should be immersed in the Saturated KCl solution for good results. The potential difference between the two electrodes should be just few millivolts (very close to ZERO Volts).