Carsten Streb, professor of chemistry at Johannes Gutenberg University Mainz, is leading a line of research that tackles two persistent challenges in energy and chemical engineering at once: how to produce hydrogen without carbon dioxide emissions, and how to extract value from industrial waste streams. In a study published this month in Advanced Energy Materials, Streb and his colleagues describe an electrochemical process that converts glycerol, a low-value byproduct of biodiesel production, into hydrogen and formate using a newly designed catalyst system.
Chala, S. A., Oseghe, E. O., Lakshmanan, K., Langer, M., Potemkin, K., Heim, P., Liu, R., Studer, T. R., Tsai, M., Cao, K., Chang, Chun‐Chi, Chang, Chia‐Yu, Sowa, K., Ebrahimi, E., Rahali, S., Clausing, S. T., Akbari, S. S., Bansmann, J., Hwang, B. J., & Streb, C. (2026). Molecular Bottom‐Up Design of Single‐Site Copper‐Palladium Catalysts for Selective Glycerol Electro‐Oxidation. Advanced Energy Materials. https://doi.org/10.1002/aenm.202504456
Hydrogen is widely viewed as a key component of future low-carbon energy systems, but its current production is dominated by steam methane reforming, a process that relies on fossil fuels and generates significant CO₂ emissions. At the same time, the rapid expansion of biodiesel manufacturing has created large volumes of glycerol that exceed demand in traditional markets such as pharmaceuticals and cosmetics. Converting this surplus material into useful chemical products has become an active area of research.
Carsten Streb, professor of chemistry at Johannes Gutenberg University Mainz stated,
“The approach we have devised could make a significant contribution to the electrification of the chemical industry. This is a major driver for large-scale commercial developments to reduce industrial CO2 emissions. Processes which currently require considerable amounts of petroleum or natural gas could in future be operated using sustainable electricity.”
The approach developed at Mainz builds on the well-established principle of water electrolysis, where electricity is used to split water into hydrogen and oxygen. Instead of producing oxygen at the anode, the researchers replace this reaction with the electro-oxidation of glycerol. This form of hybrid electrolysis allows hydrogen to be generated at the cathode, while glycerol is selectively converted into formate at the anode. When powered by renewable electricity, the overall process operates without direct CO₂ emissions.
Formate, the salt of formic acid, is an important intermediate in the chemical industry, used in applications ranging from leather processing to chemical synthesis. Today, it is typically produced from fossil-derived feedstocks, with associated carbon emissions. By contrast, the electrochemical pathway demonstrated by the Mainz team uses a renewable carbon source and avoids the release of carbon dioxide during conversion.
A central element of the work is the development of a new catalyst that enables the reaction to proceed efficiently and selectively. The catalyst is constructed at the molecular level, combining copper and palladium in close proximity to form isolated active sites. This configuration allows glycerol, which contains a three-carbon backbone, to be broken down stepwise into single-carbon formate units while maintaining high selectivity. According to the researchers, both experimental measurements and theoretical modeling were used to understand how the two metals cooperate during the reaction.
Similar efforts reported by other research groups in recent years have explored glycerol electro-oxidation using single-metal catalysts, often facing trade-offs between activity, selectivity, and stability. The Mainz study adds to this body of work by showing that carefully designed bimetallic systems can address several of these limitations simultaneously. Computational studies carried out in collaboration with researchers at National Taiwan University of Science and Technology helped clarify how reaction intermediates bind to the catalyst surface and how the presence of palladium influences copper’s catalytic behavior.
From an engineering perspective, the significance of the process lies in its potential integration into electrified chemical production. Hybrid electrolysis reduces the energy demand compared with conventional water electrolysis because glycerol oxidation is thermodynamically more favorable than oxygen evolution. This means that hydrogen can be produced with lower electrical input, improving overall efficiency when coupled with renewable power sources.
The research team emphasizes that further work is needed before industrial deployment. One priority is reducing reliance on palladium, a noble metal with limited availability and high cost. Ongoing studies are examining whether earth-abundant metals can partially or fully replace palladium without sacrificing performance. Another avenue under investigation is the downstream use of formate. While formate itself is valuable, its conversion into methanol through a subsequent electrochemical reduction step could open access to much larger markets, particularly in fuels and chemical manufacturing.
Taken together with parallel advances in electrochemical catalysis and renewable electricity integration, the Mainz study highlights a broader trend in chemical engineering: shifting traditional, fossil-based processes toward electrically driven systems that make use of waste carbon streams. By linking hydrogen production to glycerol valorization, the work demonstrates how energy and materials challenges can be addressed within a single process framework, offering a route toward lower-emission industrial chemistry without requiring entirely new feedstocks or infrastructures.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
