Long-lasting reference electrodes: Zinc reference electrode / Copper / Copper-copper sulfate reference electrode (CSE) / Silver / Silver-silver chloride reference electrode (Ag/AgCl)

Zinc Reference Electrode

Typically made of high-purity zinc, it offers excellent stability and conductivity. In soil and freshwater environments, the potential of the zinc reference electrode remains relatively stable, providing accurate reference potential over extended periods. With a long service life, it is suitable for long-term monitoring of corrosion conditions in underground pipelines, hydraulic structures, and more.

1. Copper / Copper Sulfate Reference Electrode (CSE)

Composed of a copper rod and copper sulfate solution, this is a widely used long-lasting reference electrode. Its potential is stable and highly accurate, performing well in neutral and alkaline soils.

For example, in the cathodic protection systems of urban gas pipelines, copper/copper sulfate reference electrodes are often used to monitor the protection potential of pipelines. Due to their stable performance, they provide a reliable reference basis for long-term pipeline protection.

2. Silver / Silver Chloride Reference Electrode (Ag/AgCl)

This electrode offers high precision and stability, performing exceptionally well in environments containing chloride ions, such as seawater. Its electrode potential is less affected by temperature and remains stable across a wide temperature range.

For instance, in marine engineering, such as the anti-corrosion monitoring of steel structures on offshore oil platforms, silver/silver chloride reference electrodes are widely used. They provide a stable reference potential over the long term, delivering accurate control signals for the platform's cathodic protection system.

Long-lasting Structural Composition:

Copper Electrode: Typically made of copper with a purity of no less than 99.7%, ensuring good conductivity and chemical stability.

Saturated Copper Sulfate Solution: Serves as the electrolyte, providing a medium for ion conduction and ensuring smooth electrode reactions.

Permeable Membrane: Made of highly permeable microporous materials, such as ceramics, which allow ions to pass through while preventing solution leakage, maintaining ion exchange balance between the electrode's interior and the external environment.

Insulating Shell: Protects the electrode and prevents external interference. Typically made of pressure-resistant and corrosion-resistant materials like PVC or PPR.

Working Principle: Based on the reversible chemical reaction between copper and copper sulfate to generate a stable potential as a reference. When the electrode is inserted into the solution to be measured, copper ions undergo redox reactions on the electrode surface, exchanging with ions in the solution to form a dynamic equilibrium, thereby producing stable potential readings.

Features and Advantages:

Stable Potential: Special materials and structural design ensure the permeability of copper sulfate and ion exchange, guaranteeing the stability of the reference electrode's potential. Potential stability is typically controlled within ±20mV, and even under polarization currents below 5uA, potential fluctuations remain less than ±30mV.

Long Lifespan: Due to its unique design and material selection, the long-lasting copper sulfate reference electrode has an extended service life. It can be used for several years at room temperature, even up to 10 years, reducing the need for frequent replacements and lowering usage costs.

Easy Maintenance: Generally requires minimal maintenance. For example, some designs allow for replenishing water by irrigating the buried environment to maintain normal operation. Additionally, the electrode cap is screw-connected to the electrode cavity, making it easy to refill the solution. A single refill can last for over a year.

Wide Applicability: Widely used in various electrochemical measurements and cathodic protection systems, including measurements and monitoring in soil media. They can be used to test the polarization potential of structural steel to reflect its corrosion condition, making them essential tools in the field of metal corrosion and protection.

High Measurement Accuracy: Provides a stable potential baseline, making electrochemical measurements more accurate. This is particularly important for applications requiring high-precision measurements.