Producing "green" hydrogen from water from the Meuse River? It's now possible!

An international team of chemistry researchers, led by Dr. Laroussi Chaabane and Prof. Bao-Lian Su, has just demonstrated that it is possible to produce "green" hydrogen using natural water and sunlight. These findings have been published in the prestigious Chemical Engineering Journal.

Faced with climate change, pollution, and energy shortages, the search for alternatives to fossil fuels has become a global priority in order to achieve carbon neutrality by 2050. Among the solutions being considered, green hydrogen appears to be a particularly promising energy carrier: it has a high energy density and can be produced without greenhouse gas emissions. Today, most of the world's hydrogen (around 87 million tons produced in 2020) is obtained through costly and polluting electrochemical processes, mainly used by the chemical industry or fuel cells. Hence the major interest in more sustainable methods.

Producing hydrogen and oxygen directly from water using light, a process known as photocatalysis of water, is often referred to as the "Holy Grail of chemistry" because it is so complex to master. At the University of Namur, researchers at the Laboratory of Inorganic Materials Chemistry (CMI), part of the Nanomaterials Chemistry Unit (UCNANO) and the Namur Institute of Structured Matter (NISM), have taken a decisive step forward. They have demonstrated that it is possible to use natural water, and no longer just ultrapure water, to produce green hydrogen under the action of sunlight.

The new material developed is a three-dimensional (3D) photocatalyst based on titanium oxide, graphene, and gold nanoparticles. This 3D architecture allows for better light absorption and more efficient generation of free electrons, which are essential for triggering the water dissociation reaction. One of the main challenges lies in the use of natural water, which contains minerals, salts, and organic compounds that can disrupt the process. To address this challenge, the researchers tested their device with water from several Belgian rivers: the Meuse, the Sambre, the Scheldt, and the Yser.

The performance achieved is almost equivalent to that measured with pure water.  

This is a first in Belgium, opening up concrete prospects for the sustainable use of local natural resources!

The full article, "Synergistic four physical phenomena in a 3D photocatalyst for unprecedented overall water splitting," is available in open access.

This scientific breakthrough also earned Dr. Laroussi Chaabane the award for best poster at the 4th International Colloids Conference (San Sebastián, Spain, July 2025), highlighting the impact and originality of this work.

An international research team

• University of Namur, Faculty of Sciences, UCNANO, Laboratory of Inorganic Materials Chemistry (CMI) and Namur Institute of Structured Matter (NISM), Belgium | Principal Investigator (PI) | Professor Bao Lian SU; Postdoctoral Researcher | Dr. Laroussi Chaabane
• Institute of Organic Chemistry, Phytochemistry Center, Academy of Sciences, Bulgaria
• Department of Organic Chemistry (MSc), Loyola Academy, India
• Free University of Brussels (ULB) and Flanders Make, Department of Applied Physics and Photonics, Brussels Photonics, Belgium
• University of Quebec in Montreal (UQAM), Department of Chemistry, Montreal, Quebec, Canada
• National Institute for Scientific Research - Energy Materials Telecommunications Center (INRS-EMT), Varennes, Quebec, Canada
• Wuhan University of Technology, National Laboratory for Advanced Technologies in Materials Synthesis and Processing, China

At this stage, the study constitutes proof of concept demonstrating the feasibility of the process. It illustrates the excellence of chemical engineering and nanomaterials research at UNamur, as well as its potential for sustainable energy applications. A new study is underway to evaluate the performance of the process with seawater, a key step towards large-scale green hydrogen production.

The analyses carried out were made possible thanks to the equipment available at UNamur's Physico-Chemical Characterization (PC²), Electron Microscopy, and Material Synthesis, Irradiation, and Analysis (SIAM) technology platforms. UNamur's technology platforms house state-of-the-art equipment and are accessible to the scientific community as well as to industries and companies. 

The authors would like to thank the Wallonia Public Service (SPW) for its ongoing commitment to scientific research and innovation in Wallonia, enabling UNamur to develop technological solutions with a significant societal and environmental impact.

From fundamental to applied research, UNamur demonstrates every day that research is a driver of transformation. Thanks to the commitment of its researchers, the support of its partners from all walks of life, funders, industrial partners, and a solid ecosystem of valorization, UNamur actively participates in shaping a society that is open to the world, more innovative, more responsible, and more sustainable.