1. Hydrogen Gas Supply: Hydrogen gas is supplied to the anode (negative electrode) of the fuel cell.
2. Oxygen Gas Supply: Oxygen gas is supplied to the cathode (positive electrode) of the fuel cell.
3. Hydrogen Ion Exchange: At the anode, hydrogen molecules (H2) are split into hydrogen ions (H+) and electrons (e-). The hydrogen ions pass through the electrolyte membrane, while the electrons are directed through an external circuit, creating an electric current.
4. Oxygen Reduction: At the cathode, oxygen molecules (O2) accept electrons from the external circuit and combine with hydrogen ions (H+) from the electrolyte to form water (H2O).
5. Electrolyte: The electrolyte membrane in the fuel cell allows hydrogen ions to pass through while preventing the mixing of hydrogen and oxygen gases. Some common electrolyte materials include proton exchange membranes (PEM) or alkaline electrolytes.
6. Electrical Circuit: The electrons produced at the anode travel through the external circuit, generating an electric current. This current can power various devices or be stored in batteries for later use.
7. Water Production: As a byproduct of the reaction, water molecules are produced at the cathode. The water can be safely released as pure water vapor or collected for other uses.
Overall, the chemical reaction in a hydrogen-oxygen fuel cell can be summarized as:
2H2 (g) + O2 (g) → 2H2O (l) + Electrical Energy
Hydrogen-oxygen fuel cells are highly efficient in converting chemical energy into electrical energy, with efficiencies reaching up to 60%. They are also environmentally friendly, emitting only water as a byproduct, and are considered a promising technology for clean energy applications, such as powering vehicles, generating electricity, and providing backup power systems.
