Hydrogen Fuel Cell (PEM)
2H2 + O2 → 2H2O
Overview
In a proton exchange membrane (PEM) fuel cell, hydrogen is oxidized at the anode and oxygen is reduced at the cathode, separated by a Nafion membrane. Protons pass through the membrane while electrons flow through an external circuit, producing electricity, water, and heat. Efficiency is 40–60%, roughly double that of combustion engines.
Participants
| Role | Substance | Coefficient | State |
|---|---|---|---|
| Product | Water H₂O | 2 | (l) |
Everyday Example
Toyota Mirai and Hyundai Nexo are hydrogen fuel cell cars that emit only water vapor from their tailpipes.
Industrial Importance
Fuel cells power buses, forklifts, data center backup, and submarines. Global fuel cell revenue exceeds $5 billion and is growing rapidly.
Properties
- Type
- Electrochemical
- Reversible
- Yes
- Energy
- Exothermic
- ΔH
- -572.0 kJ/mol
- Catalyst
- Platinum on carbon
Related Reactions
Alkaline Battery Discharge
Anodizing of Aluminum
Cathodic Protection (Zinc Sacrificial Anode)
Chlor-Alkali Electrolysis
Chrome Electroplating
Copper Electroplating
Daniell Cell (Zinc-Copper Galvanic Cell)
Electrochemical CO₂ Reduction to CO
Electrochemical Machining (ECM)
Electrolysis of Molten NaCl (Downs Process)
Frequently Asked Questions
What is the equation for Hydrogen Fuel Cell (PEM)?
The balanced equation is: 2H₂ + O₂ → 2H₂O.
What type of reaction is Hydrogen Fuel Cell (PEM)?
Hydrogen Fuel Cell (PEM) is a electrochemical reaction. It is reversible under certain conditions.
Is Hydrogen Fuel Cell (PEM) exothermic or endothermic?
Hydrogen Fuel Cell (PEM) is exothermic (releases energy). The enthalpy change (ΔH) is -572.0 kJ/mol.
What conditions are needed for Hydrogen Fuel Cell (PEM)?
This reaction requires a catalyst (Platinum on carbon).