Researchers at Chalmers University of Technology in Sweden have demonstrated a new way to produce hydrogen using sunlight and water without relying on scarce platinum.

The breakthrough could lower costs and environmental impacts while accelerating the role of green hydrogen in cutting emissions.

Hydrogen is vital for decarbonising industry and transport, but current solar-driven methods depend on platinum as a co-catalyst.

Platinum is scarce, environmentally damaging to mine, and concentrated in a few countries, creating supply risks and higher costs.

In a study published in Advanced Materials, the Chalmers-led team used tiny particles of electrically conductive plastic to drive photocatalysis.

When immersed in water and exposed to light, the particles trigger hydrogen production efficiently and at low cost.

“Developing efficient photocatalysts without platinum has been a long-standing dream in this field,” said Alexandre Holmes, joint first author of the study.

“By applying advanced materials design to our conducting-plastic particles, we can produce hydrogen efficiently and sustainably without platinum – at radically lower cost, and with performance that can even surpass platinum-based systems.”

The researchers improved performance by redesigning the plastic at molecular level to make it more compatible with water. They also formed it into nanoparticles, increasing contact between light, water and the catalyst.

“With as little as one gram of the polymer material, we can produce 30 litres of hydrogen in one hour,” Holmes said.

The team also notes that the plastic itself can now be produced without harmful chemicals, further improving sustainability and scalability.

This supports wider deployment of solar hydrogen as a low-emissions energy carrier.

The next step is to eliminate the need for added helper chemicals and use only sunlight and water to split molecules into hydrogen and oxygen.

Research leader Professor Ergang Wang said: “Removing the need for platinum in this system is an important step towards sustainable hydrogen production for society.”

If fully scaled, the approach could support clean fuel production for industry, storage and heavy transport, helping cut emissions where electrification is difficult.