Why are inert anodes used in some marine applications?

Inert anodes are employed in marine applications primarily because they are designed to provide cathodic protection without themselves dissolving into the surrounding environment. This characteristic is crucial, particularly in applications where the long-term integrity of the anode is required, as they do not contribute to additional corrosion or pollution in the water.

Inert anodes, commonly made from materials like titanium or conductive ceramics, function by providing a surface for the cathodic protection process to occur. During this process, they facilitate the transfer of electrons while remaining largely intact over time. This contrasts with expendable sacrificial anodes, which corrode and gradually diminish as they protect other metal components.

The other options focus on different aspects and functionalities that do not align with the primary purpose of inert anodes in corrosion prevention. For example, while some anodes do provide protection while degrading, inert anodes specifically avoid this degradation process, highlighting their unique role in stability and long-term effectiveness.