Platinum-free breakthrough paves way for cheaper green hydrogen

Researchers at Chalmers University of Technology in Sweden have unveiled a major advance that could significantly cut the cost of green hydrogen by eliminating the need for platinum, one of the most expensive and scarce materials used in solar hydrogen production. The findings, published in Advanced Materials, demonstrate that hydrogen can be produced from sunlight and water using nanoparticles made from electrically conductive plastic instead of platinum-based co-catalysts.

Green hydrogen is widely viewed as a key pillar of future clean energy systems because it releases only water when used. But, large-scale production has remained expensive and resource-intensive, largely due to dependence on platinum. Platinum is not only costly and environmentally damaging when dug out, but is also concentrated in a handful of countries, raising supply and geopolitical risks.

The Chalmers-led team has shown that platinum is no longer essential for efficient photocatalytic water splitting. By using conjugated polymers—plastics that can conduct electricity and absorb sunlight—the researchers achieved hydrogen production rates that can rival, and in some cases exceed, those of platinum-based systems.

The breakthrough came from redesigning the polymer material at the molecular level. Researchers modified the structure of the polymer chains to make them more hydrophilic and loosely packed, allowing better interaction with water and more efficient absorption of sunlight. These polymers were then formed into nanoparticles, further enhancing performance.

In laboratory tests under simulated sunlight, the plastic nanoparticles immediately began producing visible hydrogen bubbles. According to the research team, just one gram of the polymer can generate up to 30 litres of hydrogen per hour under experimental conditions.

The advance is further strengthened by parallel research showing that the conductive plastic can be produced without toxic chemicals and at much lower cost, improving sustainability across the entire supply chain. While the current system still relies on vitamin C as an additive to maintain reaction speed, researchers are now working toward complete water splitting using only sunlight and water.

If successful, the technology could pave the way for scalable, low-cost solar hydrogen production without reliance on rare or geopolitically sensitive metals, accelerating the global clean energy transition.