Solar Hydrogen Can Now Be Produced Efficiently without the Scarce Metal Platinum

January 12, 2026

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(Chalmers University of Technology/EurekAlert!) A research team led by Chalmers University of Technology, Sweden, have presented a new way to produce hydrogen gas without the scarce and expensive metal platinum. Using sunlight, water and tiny particles of electrically conductive plastic, the researchers show how the hydrogen can be produced efficiently, sustainably and at low cost.

Hydrogen plays a key role in the global pursuit for renewable energy. Although its use produces only water as a by-product, significant challenges remain before hydrogen can be produced both on a large-scale and in an environmentally friendly way.

A major challenge is the use of the metal platinum as a co-catalyst when sunlight and water are used to produce hydrogen. The Earth’s reserves of platinum are limited, and extraction is associated with risks to both the environment and to human health. Moreover, the production is concentrated in only a few countries, for example South Africa and Russia.

In a new study, published in the scientific journal Advanced Materials, a research team led by Professor Ergang Wang at Chalmers, show how solar energy can be used to produce hydrogen gas efficiently – and completely without platinum.

The process, Chalmers researcher Alexandre Holmes explains, involves quantities of tiny particles of electrically conductive plastic. Immersed in water, the particles interact both with sunlight and with their surroundings.

"Developing efficient photocatalysts without platinum has been a long-standing dream in this field. 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", says Holmes, who together with Jingwen Pan from Jiefang Zhu’s group at Uppsala University, is the joint first author of the paper.

Cured fear of water behind the success

Efforts to overcome the platinum bottleneck have been underway for several years in Wang's research group at Chalmers.

The key to the new approach lies in advanced materials design of the electrically conductive plastic used in the process. This type of plastic, known as conjugated polymers, absorbs light efficiently, but is typically less compatible with water.

By adjusting the material properties at the molecular level, the researchers made the material much more water compatible.

“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. The improvement comes from more loosely packed, more hydrophilic polymer chains inside the particles”, says Holmes.

In the reactor at the chemistry laboratory at Chalmers, bubbles of hydrogen gas can be easily seen with the naked eye as they form – showing that photocatalysis is happening efficiently.

When a lamp with simulated sunlight is directed at a beaker of water containing the nanoparticles, small bubbles of hydrogen gas almost immediately begin to form and rise through the water. The bubbles are collected and guided through tubes to a storage container, and the amount of gas produced can be monitored in real time.

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

Not only that, a recently published breakthrough from research colleagues at Chalmers shows that the electrically conductive plastic can also be produced without the use of harmful chemicals and in a much more cost-effective way.

Avoiding another expensive ingredient: vitamin C

The next major step for Wang’s group will be to make the hydrogen process work using only sunlight and water, without any added helper chemicals.

Currently, they use vitamin C, which acts as a so-called sacrificial antioxidant. By donating electrons, it prevents the reaction from stalling, which in the laboratory can show high hydrogen production rates.

To realise truly sustainable solar hydrogen, Professor Wang explains, the goal is to split water molecules into hydrogen and oxygen simultaneously, with sunlight and water as the only inputs.

“Removing the need for platinum in this system is an important step towards sustainable hydrogen production for society. Now we are starting to explore materials and strategies aimed at achieving overall water splitting without additives. That will need a few more years, but we believe we are on the right track”, says research leader Ergang Wang, professor at the Department of Chemistry and Chemical Engineering at Chalmers.

High-resolution images and a video clip from the lab can be downloaded via this link.

More about electrically conductive plastic:

Electrically conductive plastic is also known as conjugated polymers. Conjugated polymers are semiconducting materials analogous to inorganic semiconductors such as silicon. This semiconducting nature makes it possible to manufacture a new type of technology – organic electronics – which can be used in many different areas such as energy conversion and storage, wearable electronics, electronic textiles and biotechnology in connection with or near the body.

Research has been conducted for a long time to make conjugated polymers stable and improve their electrically conductive properties.

The discovery that certain types of plastic can conduct electricity was made in the 1970s and was awarded the Nobel Prize in Chemistry in 2000. The laureates were Alan J. Heeger, Alan G. MacDiarmid and Hideki Shirakawa.

Briefly about hydrogen:

Hydrogen is an energy carrier that is used to transport, store and provide energy, just like electricity. Hydrogen can be produced from different types of energy sources: fossil, fossil-free, renewable. Hydrogen has great potential in renewable energy systems, where it can produced from, for example, sunlight or wind. Hydrogen is currently used worldwide to store solar and wind power, make homes self-sufficient in energy and as a vehicle fuel without harmful emissions.

Related articles

Highly Efficient Platinum-Free Photocatalytic Hydrogen Evolution From Low-cost Conjugated Polymer Nanoparticles (Advanced Materials)
The recipe that lets electrically conductive plastic connect your body (Chalmers University of Technology)
Open-flask, ambient temperature direct arylation synthesis of mixed ionic-electronic conductors (Science Advances)

Excerpt from Chalmers University of Technology: Electrically conductive plastic is a material that can be used for everything from sensors that monitor our health to self-cooling clothing or electronic stickers on the skin that send values directly to your mobile phone. Now researchers at Chalmers present a groundbreaking recipe for making it easier to manufacture the sought-after plastic in larger quantities and without toxic chemicals – in a more cost-effective way.

“When we get up to volume, we can work with the material in a completely different way. Larger quantities are required to be able to develop the various areas of use that exist, for example in biotechnology, energy storage and portable electronics,” says Christian Müller, professor at the Department of Chemistry and Chemical Engineering and scientific leader of a study recently published in Science Advances.

In the lab in the chemistry building at Chalmers, doctoral student Joost Kimpel shows the gold-glittering mass that can be easily shaped by gloved fingers. One hundred grams of the electrically conductive plastic would cost around one million kronor on the market today; about ten times as much as real gold. But for the human body, it is precisely the absence of metals that makes the material so valuable.

– While some metals can rust in humid environments, electrically conductive plastic is an organic material that feels good in the body and that the body feels good with. The material is reminiscent of the body's own tissues, while being a semiconductor. It is also an environmental advantage that you do not need to use the rare earth metals required for today's electronics, says Joost Kimpel, lead author of the new study.

Connected electronic stickers

There is great interest in electrically conductive plastics, or conjugated polymers as they are scientifically known, and their applications are numerous – not least in biotechnology. According to the researchers, these could include sensors that monitor disease states, provide information about fitness and health, or deliver drugs for difficult-to-treat diseases. With such technology, the body can be connected to other portable electronics, and even our mobile phones.

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Unexpected lab result behind the progress

The key to the new manufacturing method, however, was found by a happy accident – during a routine experiment in the lab. When a chemical reaction went too fast and the plastic became ready too quickly, the idea of lowering the heat in the process came up. This was the starting point that led to the material now being manufactured at room temperature – in significantly fewer steps, with lower energy consumption and without toxic chemicals.

– The ingredients in our “recipe” are mild and can be used in industry, unlike the highly toxic substances that must be used today. Avoiding toxins in manufacturing means a safer working environment for staff, gives consumers peace of mind and facilitates recycling. In addition, costs can be radically reduced, since toxic substances require advanced handling, not least when it comes to protective procedures, storage and disposal of residual products, says Joost Kimpel.

Great interest in the new method

Although the study is brand new, the researchers have already noticed a lot of interest, not least because many researchers from other universities have gotten in touch. They now hope that the new manufacturing method will be able to bring electrically conductive plastic into society.

– An important discovery from this study is that the production method makes the electrically conductive plastic much better, which also means that electronics using these materials can become more powerful, says Christian Müller.

The next step in the research will be to work further on a method that makes it possible to produce even larger volumes – without interruption and with exactly the same results every time.

– The possibilities are great, but it is up to society and the market what is developed. It is a big step from lab to industry, but we hope that the new manufacturing method will be able to contribute a lot of benefit, says Christian Müller. READ MORE