Hydrogen now can be produced without the scarce and expensive metal platinum, a research team led by Chalmers University of Technology, Sweden claims, using sunlight and water, potentially removing one of the biggest cost and sustainability bottlenecks in green hydrogen production. The work, published in Advanced Materials, replaces platinum co-catalysts with nanoparticles made from electrically conductive plastic—materials that are cheaper, more abundant and easier to scale.
Hydrogen is widely seen as a cornerstone of future clean energy systems because it emits only water when used. But producing it sustainably and at scale remains difficult. One major hurdle has been the reliance on platinum in photocatalytic systems that split water using sunlight. Platinum is scarce, environmentally costly to mine, and geographically concentrated in a few countries such as South Africa and Russia.
In the new study, the Chalmers-led team demonstrates that platinum is no longer essential.
“Developing efficient photocatalysts without platinum has been a long-standing dream in this field,” says Alexandre Holmes, a researcher at Chalmers and joint first author of the paper. “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.”
How plastic replaces platinum
The process relies on conjugated polymers—electrically conductive plastics that absorb sunlight efficiently. Traditionally, these materials have performed poorly in water, limiting their usefulness for solar hydrogen.
The breakthrough came from redesigning the material at the molecular level. By making the polymer chains more hydrophilic and loosely packed, the researchers improved how the particles interact with water and light.
“We also developed a way to form the plastic into nanoparticles that can enhance the interactions with water and boost the light-to-hydrogen process,” Holmes explains. “The improvement comes from more loosely packed, more hydrophilic polymer chains inside the particles.”
