There are three primary types of electrodes in electrochemical measurements:

• Working Electrode (WE): The electrode where the electrochemical reaction of interest takes place.
• Counter Electrode (CE): Also called the auxiliary electrode, it completes the electrical circuit by allowing current to flow in the cell.
• Reference Electrode (RE): Provides a stable and known potential against which the working electrode potential is measured. Common types include:
  • Silver/Silver Chloride (Ag/AgCl)
  • Saturated Calomel Electrode (SCE)
  • Mercury/Mercurous Sulfate Electrode (MSE)

Reference solutions are used to maintain the stability of the reference electrode and ensure accurate potential measurements. Common solutions include:

• Saturated KCl (Potassium Chloride) for Ag/AgCl reference electrodes.
• Saturated KCl(Potassium Chloride).
• Buffer solutions for pH control in certain applications.

These solutions are essential for keeping the reference electrode’s potential constant over time.

Foils are used in a variety of electrochemical applications, including:

• Corrosion Studies: Metal foils are often used to study the corrosion behavior of materials in different electrolytes.
• Electrode Materials for Sensors: Foils are sometimes modified to create sensitive electrodes for detecting gases, ions, or biomolecules.
• Fuel Cells and Batteries: Nickel, platinum, and carbon-based foils are used as electrodes in fuel cells and in the development of lithium-ion batteries.
• Supercapacitors: Carbon-based foils are widely used as electrode materials in supercapacitors due to their high surface area and good electrical conductivity.
• Electroplating and Electrolysis: Foils serve as substrates in electroplating and other electrolysis-based applications.

To maintain an electrochemical cell:

• Clean the electrodes after each use to prevent contamination.
• Check the electrolyte for any signs of contamination or degradation, and replace it as needed.
• Inspect the salt bridge or separator for blockages or damage.
• Store the cell properlyto avoid contamination or electrode corrosion (e.g., store in a dry environment or under inert gas if necessary).

A Proton Exchange Membrane (PEM) is a type of ion-exchange membrane that selectively allows protons (H⁺ ions) to pass through it while blocking electrons and other ions. PEMs are commonly used in Proton Exchange Membrane Fuel Cells (PEMFCs), electrolyzers, and other electrochemical systems where proton conductivity is essential.

An Anion Exchange Membrane (AEM) is an ion-exchange membrane that selectively allows anions (e.g., OH⁻, Cl⁻) to pass through it while blocking protons (H⁺) and other cations. AEMs are primarily used in Anion Exchange Membrane Fuel Cells (AEMFCs), alkaline electrolyzers, and other systems where the conduction of anions is required.

A corrosion cell generally consists of the following key components:

• Working Electrode (Metal Sample): The material (usually metal or alloy) whose corrosion behavior is being studied. The working electrode is typically the anode where oxidation (corrosion) occurs.
• Counter Electrode: The electrode that completes the electrical circuit, often made from inert materials (e.g., platinum or graphite).
• Reference Electrode: A stable electrode that maintains a constant potential against which the potential of the working electrode is measured. Common reference electrodes used in corrosion cells are the Saturated Calomel Electrode (SCE) or Silver/Silver Chloride (Ag/AgCl) electrode.
• Electrolyte: A conductive solution, usually an aqueous solution (e.g., NaCl, H₂SO₄, or a synthetic seawater solution), which mimics the corrosive environment. The electrolyte facilitates the ion movement between the anode and cathode.
• Cell Container: The container that holds the electrodes and electrolyte in place, usually made of non-reactive material like plastic or glass.

The reference electrode is essential because:

• It provides a stable reference potential that does not change during the course of the experiment, allowing for accurate measurements of the working electrode potential.
• It ensures precise control over the electrochemical reactions at the working electrode by allowing for the potential to be adjusted relative to a known value.
• It enables the measurement of electrode potentials in systems with varying concentrations, compositions, or environmental conditions.
• It allows for the comparison of results across different experiments by using a standard reference.

A doctor blade is a flat, rigid tool (often made from stainless steel or other durable materials) that is used to spread or scrape a thin layer of material onto a substrate surface. The blade is typically placed at a specific angle relative to the surface and moved across the material to create a uniform coating. It is commonly used in the production of thin films, especially in applications where precise control over thickness is critical, such as in electrochemical sensors, energy storage devices, and surface coatings for electrodes.

Doctor blades are versatile and can be used to apply a variety of materials, including:

• Electrode Materials: Active materials like lithium, graphite, or polymers used in lithium-ion batteries, supercapacitors, and other energy storage devices.
• Conductive Inks: Ink-based formulations that include conductive materials (such as carbon nanotubes, graphene, or silver nanoparticles) used for printed electrodes or electrochemical sensors.
• Catalyst Layers: Precious metal catalysts (such as platinum, palladium, or gold) used in fuel cells or electrolysis applications.
• Polymer Coatings: Polymers or composites that form protective layers in various electrochemical devices, like conducting polymers for sensors or batteries.
• Electrolyte Layers: Thin films of solid or gel electrolytes in solid-state batteries or supercapacitors.