Researchers at the German Fraunhofer Institute have developed an innovative modular solution that uses semiconductor coatings on glass to efficiently produce clean hydrogen energy from sunlight. This technology, known as the tandem PEC module, combines the photoelectrochemical process with photovoltaic elements to generate hydrogen without the need for separate electrolysis.
How the Tandem PEC Module Works
The tandem PEC module is coated with semiconducting materials on both sides of standard float or plate glass. When sunlight hits the glass:
- Short-wavelength light is absorbed on one side of the module
- Long-wavelength light passes through and is absorbed on the reverse side
- Hydrogen is released on the cathode (reverse) side
- Oxygen is released on the anode (upper) side
- Strict separation between hydrogen and oxygen is maintained for safety
High-Purity Semiconductor Materials and Ultra-Gentle Coating Methods
Fraunhofer scientists developed high-purity semiconductor materials applied using ultra-gentle coating methods. These nanometre-thick layers, formed using vapor phase techniques, have optimized properties and structures that significantly impact the reactor’s activity and efficiency.
Efficient and Modular Hydrogen Generation
The resulting reactor has an active surface area of half a square meter and can generate over 30 kilograms of hydrogen per year over 100 square meters under European sunlight conditions. The compact modules can be connected as needed, allowing for flexibility in scaling.
The Future of Clean Hydrogen Energy
Fraunhofer’s semiconducting glass technology offers a promising solution for the efficient generation of clean hydrogen energy from sunlight. As the demand for renewable energy sources grows, this modular and scalable approach could play a significant role in the transition to a more sustainable future.