Introduction
Electrode coatings are crucial for enhancing the performance and durability of electrodes used in a wide range of industrial applications. These coatings are designed to improve the electrode’s ability to resist corrosion, wear, and other forms of degradation, thereby extending their service life and reducing maintenance costs. Precious metals are often employed as the coating materials for electrodes due to their excellent electrical and thermal conductivity, as well as their resistance to oxidation and other forms of corrosion. Here, this article is going to discuss various precious metals commonly used for electrode coatings. Hope that you can have a further comprehension of the features and applications of these noble metals.

Precious Metal Materials for Electrode Coatings
Precious metals are not only characterized by their aesthetic appeal and economic values but also by their excellent physical properties. Gold, silver, platinum, and other precious metals are widely applied to electrodes for their corrosion resistance, conductivity, and strength. One of their main disadvantages is the relatively high cost, making it impossible to use pure precious metals to make electrodes. Applying precious metals as thin-film coatings on electrodes is an economical alternative that maintains the good properties of precious metals with a smaller budget.
Here are some of the most commonly used precious metals for electrode coatings.
Gold
Gold is a popular precious metal employed in electrode coatings due to its excellent electrical and thermal conductivity. This metal also has resistance to corrosion that it won’t react with water, air, and oxygen.
With these desirable properties, gold is used for coating electrodes that require high levels of accuracy and precision, such as medical devices and electronics.
Silver
Silver is a cost-effective coating material compared with other precious metals. It also has impressive conductivity and corrosion resistance. Silver is known for its highest thermal and electrical conductivity of all metals. Additionally, its excellent resistance to oxidation and corrosion makes it ideal for use in harsh surroundings.
Therefore, you can find this highly conductive metal as electrode coatings for electrical contacts, solar cells, and medical implants. However, please remember to avoid utilizing silver in humid environments because cracking might happen.
Platinum
Platinum is a highly durable and corrosion-resistant metal. The excellent electrical conductivity and catalytic activity make it a perfect material for enhancing the performance of electrodes used in electrochemical reactions. This metal is also extremely stable and does not react with most chemicals at high temperatures, making platinum ideal for the automotive and aerospace industries in various applications. It is also applied to make electrode coatings for fuel cells, sensors, and electrochemical devices.
Others
- Palladium
Palladium is a versatile and highly durable electrode coating material used in hydrogen sensors, fuel cells, and catalysis for its excellent ability to absorb and release hydrogen.
- Ruthenium
Ruthenium is often used in electrode coatings for applications such as supercapacitors, batteries, and electrocatalysis. Its high conductivity and catalytic activity can enhance the performance of electrodes used in electrochemical reactions.
Specific Applications of Precious Metals for MMO Electrode Coating
Precious metal coatings are commonly employed for mixed metal oxide (MMO) electrodes. These electrodes come with high conductivity and corrosion resistance, which account for their stable performance and longer lifetime. MMO electrodes are widely used as anodes in electrolytic cells for chlorine production, printed circuit board manufacturing, etc.
Take the case of chlorine preparation for example. Using MMO electrodes as anodes for chlorine evolution can reduce the consumed energy. This is because the electrodes with precious metals coatings come with lower anode overpotential, further reducing the cell voltage and power consumption. Therefore, the energy costs would be reduced, and the manufacturing process would be more environmentally friendly.

Conclusion
In a word, precious metals are highly valued for their excellent electrical and thermal conductivity, resistance to corrosion and wear, and other desirable properties. They are often used for electrode coatings in a wide range of industrial applications. Platinum, gold, silver, palladium, and ruthenium are some of the most commonly used precious metals for electrode coatings due to their unique properties.
Stanford Advanced Materials (SAM) has rich experience in the manufacture and sale of precious metal coating materials at reasonable prices. Send us an inquiry if you are interested.
Reference:
[1] Platinum. (2023, April 10). In Wikipedia. https://en.wikipedia.org/wiki/Platinum
[2] Li Y, Li S, Zhang C, Xu N, Bao Z. Oxidation Behavior and Oxide Transformation of a Pt-Modified Aluminide Coating at Moderate High Temperature. Crystals. 2021; 11(8):972. https://doi.org/10.3390/cryst11080972