A team of scientists from Imperial College London and Queen Mary University of London has developed an innovative solar-powered device that produces hydrogen fuel directly from water using only sunlight and inexpensive, widely available materials. Published in the journal Nature Energy, this breakthrough technology has the potential to significantly lower the cost of producing clean hydrogen fuel, providing a promising pathway toward a more sustainable and renewable energy future.
Hydrogen fuel is widely regarded as a key component of the clean energy transition, as it produces only water vapor when used and can serve as a zero-emission fuel for transportation, heating, and industrial processes. However, most hydrogen today is produced from natural gas through a process called steam methane reforming, which releases large amounts of carbon dioxide — approximately nine kilograms of CO₂ for every kilogram of hydrogen generated. This reliance on fossil fuels undermines hydrogen’s potential as a truly green energy carrier.
While solar-powered hydrogen production offers an environmentally friendly alternative by using sunlight to split water molecules into hydrogen and oxygen, existing technologies face significant hurdles. Many current systems rely on rare, expensive materials like platinum or iridium, which not only increase costs but also degrade quickly when in contact with water, limiting the lifespan and practical application of these devices.
To overcome these limitations, the UK research team designed a novel multi-layer solar water-splitting device. Their innovative approach combines organic, plastic-like materials—known for their ability to absorb sunlight efficiently—with a protective graphite layer coated with nickel and iron catalysts. Both nickel and iron are abundant, affordable metals, making the system much more cost-effective and scalable than previous solutions.
Dr. Flurin Eisner from Queen Mary University explains, “Our findings demonstrate that it’s possible to achieve efficient and durable solar water splitting with low-cost, scalable organic materials.” The organic materials used in the device are highly versatile and can be engineered to capture various wavelengths of sunlight. This adaptability allows the system to perform well under different lighting conditions and geographic locations.
The device functions by absorbing sunlight with its organic layer, which generates electricity. This electrical energy then powers a chemical reaction catalyzed by the nickel and iron coatings, splitting water molecules into hydrogen and oxygen gases. The graphite layer plays a crucial role as a protective barrier, preventing damage to the delicate organic materials and enhancing the system’s longevity.
The device produces an electrical current of over 25 milliamps per square centimeter, marking a significant advancement in performance compared to earlier prototypes, which typically stopped working after only a few hours. Impressively, the UK team’s system can operate continuously for several days without degradation.
Beyond the individual components, the researchers successfully constructed fully integrated systems capable of converting sunlight and water directly into hydrogen fuel at an efficiency of 5%. While 5% may appear modest compared to other energy conversion technologies, it is a noteworthy achievement in the field of solar-driven water splitting—especially considering that no external power supply is required.
Dr. Salvador Eslava from Imperial College London elaborated on the materials used: “We employed organic bulk heterojunctions—materials that generate electrical current when exposed to light and are straightforward to produce and scale up.” Unlike traditional semiconductor materials that require complex fabrication processes and expensive raw materials, these organic components can be manufactured more easily and at a lower cost, which is essential for widespread adoption.
Hydrogen produced using this solar-driven approach offers a pathway to decarbonize sectors that are currently difficult to electrify, such as heavy industry, shipping, and long-haul transport. According to industry estimates, if just 10% of the world’s hydrogen supply were generated from solar-powered devices like this, global carbon emissions could be cut by around 60 million tons annually—equivalent to taking approximately 13 million cars off the road for a year.
This technology could also transform energy access in remote or off-grid regions, where reliable electricity is scarce. With only sunlight and water, communities could generate their own clean hydrogen fuel, powering vehicles, heating systems, or even electricity generation without relying on fossil fuels or extensive infrastructure.
The researchers are now focused on further improving the stability of their device and scaling the technology for industrial use. Lead author Dr. Matyas Daboczi emphasized, “Our findings provide important insights that will help improve the durability and performance of organic photoelectrochemical devices.” Scaling up from lab prototypes to commercial-scale systems will be critical for bringing this technology to market and realizing its full potential.
If successful, this advancement could make hydrogen fuel a practical, zero-emission alternative to fossil fuels on a large scale. Additionally, solar hydrogen offers a way to store renewable energy over long periods, addressing a major challenge with solar and wind power, which can be intermittent and inconsistent.
As governments and industries worldwide seek to reduce carbon emissions and meet climate goals, innovative technologies like this will be crucial. Decarbonizing sectors such as steel manufacturing and shipping, which currently account for roughly 20% of global carbon emissions, requires alternatives beyond traditional electrification.
The UK research team’s work represents an important step toward affordable, scalable, and sustainable hydrogen production. By leveraging common materials in novel ways, they have moved closer to making clean hydrogen a widespread reality, helping to build a greener future for all.
