Periodic Reporting for period 1 - POMASAC (Photoelectrochemical Oxidation of Methane using Single Atom Catalysts)
Reporting period: 2023-12-01 to 2025-11-30
Europe’s move towards climate-neutral energy and chemical production depends on finding better ways to use simple but stubborn molecules such as methane (or unactivated sp3 C-H bonds containing alkanes) and carbon dioxide (CO2). Methane is widely available as the main component of natural gas, while CO2 is an unavoidable by-product of many industrial activities. Both are chemically stable, which makes their conversion into useful products difficult and energy-intensive. Developing catalysts that can activate these molecules efficiently, using less energy and fewer critical metals, remains a major scientific challenge.
The POMASAC project was designed to address this challenge by developing new catalyst materials in which metals are used in very small amounts, particularly as single atoms. The work focused on metal oxides and carbon-based materials, including carbon nitride single-atom catalysts, where individual metal atoms are stabilized within a solid support. These systems offer a way to maximize catalytic efficiency while reducing material costs. The project also explored novel combustion-based synthesis approaches as a fast and flexible method to create such single-site catalysts in both oxide and carbon-based organic frameworks.
The overall objective of the project was to understand how these catalysts work at a fundamental level during light and electricity-assisted (photoelectrochemical) alkane activation and CO2-related reactions. Rather than targeting an immediate commercial technology, the project focused on identifying clear links between catalyst structure, atomic arrangement (especially in bridging organometallic homogeneous catalysts to heterogeneous single atom catalysts), and chemical behaviour, with the aim of generating design principles that are directly relevant to future industrial catalyst development. This knowledge provides a solid basis for future development of more efficient and sustainable catalytic processes. By strengthening the scientific understanding of single-atom and oxide-based catalysts, POMASAC contributes to Europe’s long-term goals in sustainable chemistry and supports future innovation in low-carbon energy and chemical technologies.
The POMASAC project was designed to address this challenge by developing new catalyst materials in which metals are used in very small amounts, particularly as single atoms. The work focused on metal oxides and carbon-based materials, including carbon nitride single-atom catalysts, where individual metal atoms are stabilized within a solid support. These systems offer a way to maximize catalytic efficiency while reducing material costs. The project also explored novel combustion-based synthesis approaches as a fast and flexible method to create such single-site catalysts in both oxide and carbon-based organic frameworks.
The overall objective of the project was to understand how these catalysts work at a fundamental level during light and electricity-assisted (photoelectrochemical) alkane activation and CO2-related reactions. Rather than targeting an immediate commercial technology, the project focused on identifying clear links between catalyst structure, atomic arrangement (especially in bridging organometallic homogeneous catalysts to heterogeneous single atom catalysts), and chemical behaviour, with the aim of generating design principles that are directly relevant to future industrial catalyst development. This knowledge provides a solid basis for future development of more efficient and sustainable catalytic processes. By strengthening the scientific understanding of single-atom and oxide-based catalysts, POMASAC contributes to Europe’s long-term goals in sustainable chemistry and supports future innovation in low-carbon energy and chemical technologies.
POMASAC focused on the design, synthesis, and mechanistic understanding of advanced catalyst materials for light-assisted alkane activation and CO2-related transformations. A central activity was the development of metal-oxide-based and carbon-based catalyst platforms in which metals are stabilized as isolated atoms, small clusters, or highly dispersed sites. These materials were prepared using flexible and reproducible synthesis strategies, especially with combustion-based (or flash-conversion) approaches, which enable controlled tuning of catalyst composition, oxidation state, and defect structure.
In parallel with alkane activation studies, the project addressed electrochemical CO2 reduction pathways enabled by flash-converted metal-oxide catalysts. These systems were shown to promote selective CO2 reduction to formate under mild electrochemical conditions. Importantly, the generated formate was identified as a reactive intermediate capable of undergoing hydrogen-atom transfer (HAT), leading to the formation of the CO2 anion radical (CO2•–) species. This reactivity opens mechanistic routes by which CO2-derived intermediates can participate in subsequent bond-forming or bond-cleavage steps, linking CO2 conversion chemistry with alkane, or alkene, or even alkyne functionalization. The use of combustion-derived metal oxides was critical in stabilizing the active redox states and defect environments required for these coupled electron-proton transfer processes.
To support methane-relevant studies and ensure realistic reaction conditions, a dedicated methane gas handling and reaction setup was designed and installed. This included the integration of methane gas cylinders, mass-flow controllers, a potentiostat, and a custom photoelectrochemical glass reactor, allowing precise control of gas composition, flow rates, and irradiation conditions. The reactor system was coupled to a micro gas chromatograph (micro-GC) for reliable, time-resolved analysis of gaseous reaction products. This infrastructure enabled safe operation, reproducible testing, and quantitative evaluation of catalytic performance under controlled gas-phase conditions.
A stepwise experimental strategy was employed to facilitate robust mechanistic insights. Liquid model alkanes were first used to investigate sp3 C–H activation pathways under light-assisted conditions, allowing detailed analysis of reaction behaviour before extending insights toward methane chemistry using the dedicated gas-phase setup. In parallel, the same catalyst-design principles were applied to CO2-related reactions, demonstrating how metal dispersion, oxide defect chemistry, and support properties influence activity and selectivity across reduction and coupled transformation pathways. Extensive physicochemical and electrochemical characterization was conducted to correlate catalyst structure with performance. Advanced spectroscopic, microscopic, and electrochemical techniques were employed to track catalyst evolution under operating conditions and to establish structure-reactivity relationships across different catalyst families, including metal-oxide-embedded systems and carbon nitride single-atom catalysts.
The main achievements of the project include the establishment of transferable design principles for single-site/atom and oxide-embedded catalysts, the development of dedicated experimental infrastructure for methane (and alkane) and CO2 studies, the generation of original catalytic and mechanistic datasets, and the construction of a coherent framework linking atomic-scale structure to redox-driven chemical behaviour. Together, these outcomes provide a strong scientific foundation for future development of scalable and industrially relevant catalytic systems that integrate CO2 utilization with hydrocarbon activation.
In parallel with alkane activation studies, the project addressed electrochemical CO2 reduction pathways enabled by flash-converted metal-oxide catalysts. These systems were shown to promote selective CO2 reduction to formate under mild electrochemical conditions. Importantly, the generated formate was identified as a reactive intermediate capable of undergoing hydrogen-atom transfer (HAT), leading to the formation of the CO2 anion radical (CO2•–) species. This reactivity opens mechanistic routes by which CO2-derived intermediates can participate in subsequent bond-forming or bond-cleavage steps, linking CO2 conversion chemistry with alkane, or alkene, or even alkyne functionalization. The use of combustion-derived metal oxides was critical in stabilizing the active redox states and defect environments required for these coupled electron-proton transfer processes.
To support methane-relevant studies and ensure realistic reaction conditions, a dedicated methane gas handling and reaction setup was designed and installed. This included the integration of methane gas cylinders, mass-flow controllers, a potentiostat, and a custom photoelectrochemical glass reactor, allowing precise control of gas composition, flow rates, and irradiation conditions. The reactor system was coupled to a micro gas chromatograph (micro-GC) for reliable, time-resolved analysis of gaseous reaction products. This infrastructure enabled safe operation, reproducible testing, and quantitative evaluation of catalytic performance under controlled gas-phase conditions.
A stepwise experimental strategy was employed to facilitate robust mechanistic insights. Liquid model alkanes were first used to investigate sp3 C–H activation pathways under light-assisted conditions, allowing detailed analysis of reaction behaviour before extending insights toward methane chemistry using the dedicated gas-phase setup. In parallel, the same catalyst-design principles were applied to CO2-related reactions, demonstrating how metal dispersion, oxide defect chemistry, and support properties influence activity and selectivity across reduction and coupled transformation pathways. Extensive physicochemical and electrochemical characterization was conducted to correlate catalyst structure with performance. Advanced spectroscopic, microscopic, and electrochemical techniques were employed to track catalyst evolution under operating conditions and to establish structure-reactivity relationships across different catalyst families, including metal-oxide-embedded systems and carbon nitride single-atom catalysts.
The main achievements of the project include the establishment of transferable design principles for single-site/atom and oxide-embedded catalysts, the development of dedicated experimental infrastructure for methane (and alkane) and CO2 studies, the generation of original catalytic and mechanistic datasets, and the construction of a coherent framework linking atomic-scale structure to redox-driven chemical behaviour. Together, these outcomes provide a strong scientific foundation for future development of scalable and industrially relevant catalytic systems that integrate CO2 utilization with hydrocarbon activation.
The project delivered advances beyond the state of the art by extending the capabilities of flash converted, single-site/atom and oxide-embedded catalyst platforms across multiple reaction classes, linking fundamental reactivity with emerging application potential.
In the area of alkane oxidation, newly developed combustion-derived electrodes enabled refined control over reaction pathways under light-assisted and electrochemical conditions. These systems allowed selective generation of oxygenated intermediates and revealed how catalyst structure and surface chemistry govern C–H activation processes. Compared to conventional oxide catalysts, the combustion-derived materials exhibited enhanced activity, scalability and stability, highlighting the advantage of rapid synthesis routes that stabilize highly dispersed active sites.
A further advance was achieved in CO2-related chemistry, where formate generation in near-neutral pH using flash converted catalysts was demonstrated under controlled electrochemical conditions. Mechanistic analyses and data validation from previous reports indicated that formate can indeed act as a precursor for hydrogen atom transfer (HAT) processes, leading to the formation of the CO2 anion radical (CO2•–). This reactive intermediate opens new transformation pathways, potentially enabling carboxylation reactions of alkanes, alkenes, and alkynes, as well as reductive dechlorination processes. However, due to the similar radical polarities, as reported in a very recent study, achieving high overall yields remains challenging and is therefore rigorously investigated in light of our new findings. These findings go beyond current state-of-the-art approaches by coupling CO2 activation with downstream carbon–carbon bond formation within a single catalytic framework. In parallel, the project achieved record-breaking performance in alkaline oxygen evolution reaction (OER) using flash converted oxide electrodes, demonstrating exceptional activity under industrially relevant conditions. Unlike many high-performing OER catalysts that rely on complex or costly synthesis routes, these materials were prepared using scalable combustion techniques, enhancing their relevance for practical deployment.
Importantly, this OER technology has progressed beyond purely academic validation. Commercialization pathways are actively being explored through the ICIQ Knowledge and Technology Transfer (KTT) office. These activities reflect the translational potential of the flash conversion scalable catalyst platform and its relevance to renewable green hydrogen production, fuel cell and electrolyzer technologies.
To support further uptake and long-term impact, key needs have been identified, including extended durability testing, scale-up and reproducibility assessment of flash conversion synthesis, and validation in device-level configurations. For results with strong exploitation potential, continued IP protection, industrial collaboration, and access to demonstration funding will be essential to bridge the gap between laboratory discovery and commercial application.
Overall, the project goes beyond the state of the art by combining new catalytic reactivity, scalable synthesis, and early-stage commercial engagement, establishing a foundation for both future fundamental research and industrial translation in sustainable catalysis.
In the area of alkane oxidation, newly developed combustion-derived electrodes enabled refined control over reaction pathways under light-assisted and electrochemical conditions. These systems allowed selective generation of oxygenated intermediates and revealed how catalyst structure and surface chemistry govern C–H activation processes. Compared to conventional oxide catalysts, the combustion-derived materials exhibited enhanced activity, scalability and stability, highlighting the advantage of rapid synthesis routes that stabilize highly dispersed active sites.
A further advance was achieved in CO2-related chemistry, where formate generation in near-neutral pH using flash converted catalysts was demonstrated under controlled electrochemical conditions. Mechanistic analyses and data validation from previous reports indicated that formate can indeed act as a precursor for hydrogen atom transfer (HAT) processes, leading to the formation of the CO2 anion radical (CO2•–). This reactive intermediate opens new transformation pathways, potentially enabling carboxylation reactions of alkanes, alkenes, and alkynes, as well as reductive dechlorination processes. However, due to the similar radical polarities, as reported in a very recent study, achieving high overall yields remains challenging and is therefore rigorously investigated in light of our new findings. These findings go beyond current state-of-the-art approaches by coupling CO2 activation with downstream carbon–carbon bond formation within a single catalytic framework. In parallel, the project achieved record-breaking performance in alkaline oxygen evolution reaction (OER) using flash converted oxide electrodes, demonstrating exceptional activity under industrially relevant conditions. Unlike many high-performing OER catalysts that rely on complex or costly synthesis routes, these materials were prepared using scalable combustion techniques, enhancing their relevance for practical deployment.
Importantly, this OER technology has progressed beyond purely academic validation. Commercialization pathways are actively being explored through the ICIQ Knowledge and Technology Transfer (KTT) office. These activities reflect the translational potential of the flash conversion scalable catalyst platform and its relevance to renewable green hydrogen production, fuel cell and electrolyzer technologies.
To support further uptake and long-term impact, key needs have been identified, including extended durability testing, scale-up and reproducibility assessment of flash conversion synthesis, and validation in device-level configurations. For results with strong exploitation potential, continued IP protection, industrial collaboration, and access to demonstration funding will be essential to bridge the gap between laboratory discovery and commercial application.
Overall, the project goes beyond the state of the art by combining new catalytic reactivity, scalable synthesis, and early-stage commercial engagement, establishing a foundation for both future fundamental research and industrial translation in sustainable catalysis.