Periodic Reporting for period 1 - ENLIVEN (hiErarchical metal-orgaNic framework@covaLent organic framework (MOF@COF) on carbon nanofIbers for electrocatalytic CO2 conVErsioN)
Période du rapport: 2023-06-01 au 2025-09-30
Climate change remains one of the most pressing global challenges, driven largely by the continued increase of greenhouse gas emissions. Among these, carbon dioxide (CO2) is a major contributor to global warming. Reaching climate neutrality by 2050, as targeted by the European Green Deal, requires not only reducing emissions, but also developing technologies that can actively capture and convert CO2 into valuable products. This approach is central to the concept of a circular carbon economy, in which waste carbon is transformed into useful chemical feedstocks and fuels, reducing our dependence on fossil resources.
The ENLIVEN project addresses this challenge by developing innovative electrocatalysts for CO2 reduction. Electrocatalysis is a promising route for converting CO2 into carbon-based fuels and chemicals using renewable electricity. However, current catalysts often face significant limitations, such as poor stability, low selectivity for multi-carbon (C2+) products, and high energy inputs. Overcoming these obstacles is essential to make CO2 electroreduction a viable industrial technology that can contribute meaningfully to Europe’s decarbonisation goals.
ENLIVEN’s strategy brings together three complementary material families to create a new class of hybrid catalysts. Copper-based metal–organic frameworks (Cu-MOFs) offer high activity and molecular tunability, making them excellent platforms for steering CO2 conversion pathways. Covalent organic frameworks (COFs) are used as protective and conductive shells that stabilise the MOFs during electrochemical operation and improve charge transport. Electrospun carbon nanofibres (CNFs) provide robust, conductive supports that ensure good electron transfer and mechanical integrity. By combining these components into hierarchical MOF@COF–CNF architectures, ENLIVEN aims to achieve catalysts that are both durable and highly selective towards C2+ products such as acetate.
The project’s specific scientific objectives are:
(1) To fabricate uniform, conductive carbon nanofibres (CNFs) as supports for electrocatalyst development;
(2) To synthesise and optimise copper-based metal–organic frameworks (Cu-MOFs) with tunable coordination environments for efficient CO2 electroreduction;
(3) To integrate covalent organic frameworks (COFs) onto MOF@CNF composites, creating stable hybrid catalysts; and
(4) To evaluate and improve their electrochemical activity, selectivity, and durability for CO2 conversion to multi-carbon (C2⁺) products. Through this work, ENLIVEN contributes to advancing key technologies for CO2 utilisation, supporting Europe’s transition towards a climate-neutral, circular economy.
Beyond scientific and technological advances, the project has strong dissemination and societal engagement components. Results are being shared through scientific conferences, peer-reviewed publications, and public outreach activities aimed at increasing awareness of sustainable CO2 conversion technologies. By connecting frontier materials research with broader environmental and policy goals, ENLIVEN supports the European Union’s strategy to mitigate climate change, foster innovation, and strengthen the continent’s leadership in green technologies.
The ENLIVEN project addresses this challenge by developing innovative electrocatalysts for CO2 reduction. Electrocatalysis is a promising route for converting CO2 into carbon-based fuels and chemicals using renewable electricity. However, current catalysts often face significant limitations, such as poor stability, low selectivity for multi-carbon (C2+) products, and high energy inputs. Overcoming these obstacles is essential to make CO2 electroreduction a viable industrial technology that can contribute meaningfully to Europe’s decarbonisation goals.
ENLIVEN’s strategy brings together three complementary material families to create a new class of hybrid catalysts. Copper-based metal–organic frameworks (Cu-MOFs) offer high activity and molecular tunability, making them excellent platforms for steering CO2 conversion pathways. Covalent organic frameworks (COFs) are used as protective and conductive shells that stabilise the MOFs during electrochemical operation and improve charge transport. Electrospun carbon nanofibres (CNFs) provide robust, conductive supports that ensure good electron transfer and mechanical integrity. By combining these components into hierarchical MOF@COF–CNF architectures, ENLIVEN aims to achieve catalysts that are both durable and highly selective towards C2+ products such as acetate.
The project’s specific scientific objectives are:
(1) To fabricate uniform, conductive carbon nanofibres (CNFs) as supports for electrocatalyst development;
(2) To synthesise and optimise copper-based metal–organic frameworks (Cu-MOFs) with tunable coordination environments for efficient CO2 electroreduction;
(3) To integrate covalent organic frameworks (COFs) onto MOF@CNF composites, creating stable hybrid catalysts; and
(4) To evaluate and improve their electrochemical activity, selectivity, and durability for CO2 conversion to multi-carbon (C2⁺) products. Through this work, ENLIVEN contributes to advancing key technologies for CO2 utilisation, supporting Europe’s transition towards a climate-neutral, circular economy.
Beyond scientific and technological advances, the project has strong dissemination and societal engagement components. Results are being shared through scientific conferences, peer-reviewed publications, and public outreach activities aimed at increasing awareness of sustainable CO2 conversion technologies. By connecting frontier materials research with broader environmental and policy goals, ENLIVEN supports the European Union’s strategy to mitigate climate change, foster innovation, and strengthen the continent’s leadership in green technologies.
The ENLIVEN project carried out a comprehensive research programme to develop and evaluate advanced hybrid catalysts for the electrochemical reduction of CO2. The work combined materials synthesis, structural and electrochemical characterisation, and catalytic testing, leading to significant scientific and technological progress.
The project began by identifying and synthesising promising copper-based metal–organic frameworks (Cu-MOFs) known for their activity in CO2 conversion. A systematic benchmarking study of several MOFs—including HKUST-1, Cu–BDC–NH2, Cu–THQ, Cu–TCPP and Zn/Co–TTFTB—was conducted to assess their electrochemical behaviour, stability, and selectivity towards different CO2 reduction products. HKUST-1 emerged as a leading candidate due to easy preparation, large density of available catalytic sites, and high selectivity towards formate.
In parallel, uniform and conductive carbon nanofibres (CNFs) were fabricated through electrospinning and carbonisation. These nanofibres provided robust, high-surface-area supports for MOF growth and facilitated efficient electron transport during electrochemical reactions. A reactive seeding strategy was developed to incorporate copper species directly into the CNFs, ensuring strong interfacial bonding between the support and the MOF layer.
Building on this platform, the project developed hybrid catalysts by coating the MOFs with covalent organic frameworks (COFs) through Schiff-base condensation reactions. This step created thin, well-defined COF shells on the MOF@CNF structures. These COF layers played a key role in improving catalyst durability and modulating the local reaction environment, which is essential for guiding selectivity.
Electrocatalytic testing of the resulting MOF@COF–CNF hybrids in CO2-saturated electrolytes demonstrated clear improvements over conventional MOFs. The hybrid catalysts showed significantly higher selectivity towards formate besides detectable formation of multi-carbon products such as acetate. The presence of the COF shell helped suppress unwanted hydrogen evolution, leading to more efficient use of electrons for CO2 conversion. The catalysts maintained over 90 % of their initial activity during extended electrochemical work, indicating excellent stability.
In addition to electrocatalysis, selected MOF systems were explored for photocatalytic applications, specifically the semi-hydrogenation of acetylene under visible light. Metalated Zn/Co–TTFTB frameworks achieved around 90 % selectivity for ethylene, illustrating the versatility of the developed materials for other environmentally relevant transformations.
Overall, ENLIVEN has demonstrated a scalable route to fabricate hierarchical MOF@COF–CNF hybrids and has provided proof-of-concept evidence for their superior performance in CO2 electroreduction. These advances represent a meaningful step towards the deployment of efficient and durable applied materials for carbon utilisation technologies.
The project began by identifying and synthesising promising copper-based metal–organic frameworks (Cu-MOFs) known for their activity in CO2 conversion. A systematic benchmarking study of several MOFs—including HKUST-1, Cu–BDC–NH2, Cu–THQ, Cu–TCPP and Zn/Co–TTFTB—was conducted to assess their electrochemical behaviour, stability, and selectivity towards different CO2 reduction products. HKUST-1 emerged as a leading candidate due to easy preparation, large density of available catalytic sites, and high selectivity towards formate.
In parallel, uniform and conductive carbon nanofibres (CNFs) were fabricated through electrospinning and carbonisation. These nanofibres provided robust, high-surface-area supports for MOF growth and facilitated efficient electron transport during electrochemical reactions. A reactive seeding strategy was developed to incorporate copper species directly into the CNFs, ensuring strong interfacial bonding between the support and the MOF layer.
Building on this platform, the project developed hybrid catalysts by coating the MOFs with covalent organic frameworks (COFs) through Schiff-base condensation reactions. This step created thin, well-defined COF shells on the MOF@CNF structures. These COF layers played a key role in improving catalyst durability and modulating the local reaction environment, which is essential for guiding selectivity.
Electrocatalytic testing of the resulting MOF@COF–CNF hybrids in CO2-saturated electrolytes demonstrated clear improvements over conventional MOFs. The hybrid catalysts showed significantly higher selectivity towards formate besides detectable formation of multi-carbon products such as acetate. The presence of the COF shell helped suppress unwanted hydrogen evolution, leading to more efficient use of electrons for CO2 conversion. The catalysts maintained over 90 % of their initial activity during extended electrochemical work, indicating excellent stability.
In addition to electrocatalysis, selected MOF systems were explored for photocatalytic applications, specifically the semi-hydrogenation of acetylene under visible light. Metalated Zn/Co–TTFTB frameworks achieved around 90 % selectivity for ethylene, illustrating the versatility of the developed materials for other environmentally relevant transformations.
Overall, ENLIVEN has demonstrated a scalable route to fabricate hierarchical MOF@COF–CNF hybrids and has provided proof-of-concept evidence for their superior performance in CO2 electroreduction. These advances represent a meaningful step towards the deployment of efficient and durable applied materials for carbon utilisation technologies.
The ENLIVEN project has achieved significant advances in the design of hybrid catalysts for CO2 electroreduction, going beyond the current state of the art in several key areas.
1. Hierarchical Hybrid Catalyst Design
Conventional CO2 electroreduction catalysts often suffer from low stability, limited selectivity for multi-carbon products, and inefficient electron transfer. ENLIVEN has addressed these limitations by integrating three distinct material classes—Cu-MOFs, COFs, and electrospun CNFs—into a single hierarchical architecture. This combination leverages the molecular tunability of MOFs, the protective and conductive properties of COFs, and the robustness of CNFs. The resulting MOF@COF–CNF hybrids are structurally well-defined and exhibit enhanced charge transport and interfacial stability, which are critical for efficient electrocatalysis.
2. Improved Selectivity and Stability
Electrochemical testing demonstrated that the hybrid catalysts achieve a significant increase in selectivity towards formate, with Faradaic efficiencies reaching around 25 %, compared to less than 10 % for pristine MOFs. The presence of COF shells also enabled partial formation of multi-carbon products such as acetate, while suppressing the competing hydrogen evolution reaction. Importantly, the catalysts maintained over 90 % of their initial activity during prolonged operation (3h), indicating a clear improvement in stability over state-of-the-art systems.
3. Versatility for Broader Applications
Beyond CO2 reduction, ENLIVEN materials were shown to be adaptable for other catalytic processes, such as the photocatalytic semi-hydrogenation of acetylene. Metalated Zn/Co–TTFTB frameworks achieved ~90 % selectivity for ethylene under visible light, highlighting the platform’s potential for multiple environmentally relevant transformations.
4. Future research and perspectives beyond academia
The project provides a strong scientific foundation for the development of next-generation CO2 conversion technologies. To ensure further uptake and success, several key steps are needed:
• Scalability: Scaling up catalyst synthesis, integrating hybrid electrodes into flow-cell systems, and evaluating long-term operation under industrially relevant conditions.
• Industrial and market engagement: Establishing partnerships with technology developers and industrial stakeholders to assess techno-economic feasibility and application potential.
• IPR and commercialisation support: Evaluating the patentability of the MOF@COF fabrication strategies and exploring licensing or spin-off opportunities.
• Regulatory and standardisation frameworks: Aligning future developments with EU sustainability regulations and standards to facilitate technology adoption.
Overall, ENLIVEN has delivered innovative materials that extend the frontiers of CO2 electroreduction research. By combining scientific excellence with clear pathways for further development, the project contributes meaningfully to the EU’s ambition to build a sustainable, climate-neutral economy.
1. Hierarchical Hybrid Catalyst Design
Conventional CO2 electroreduction catalysts often suffer from low stability, limited selectivity for multi-carbon products, and inefficient electron transfer. ENLIVEN has addressed these limitations by integrating three distinct material classes—Cu-MOFs, COFs, and electrospun CNFs—into a single hierarchical architecture. This combination leverages the molecular tunability of MOFs, the protective and conductive properties of COFs, and the robustness of CNFs. The resulting MOF@COF–CNF hybrids are structurally well-defined and exhibit enhanced charge transport and interfacial stability, which are critical for efficient electrocatalysis.
2. Improved Selectivity and Stability
Electrochemical testing demonstrated that the hybrid catalysts achieve a significant increase in selectivity towards formate, with Faradaic efficiencies reaching around 25 %, compared to less than 10 % for pristine MOFs. The presence of COF shells also enabled partial formation of multi-carbon products such as acetate, while suppressing the competing hydrogen evolution reaction. Importantly, the catalysts maintained over 90 % of their initial activity during prolonged operation (3h), indicating a clear improvement in stability over state-of-the-art systems.
3. Versatility for Broader Applications
Beyond CO2 reduction, ENLIVEN materials were shown to be adaptable for other catalytic processes, such as the photocatalytic semi-hydrogenation of acetylene. Metalated Zn/Co–TTFTB frameworks achieved ~90 % selectivity for ethylene under visible light, highlighting the platform’s potential for multiple environmentally relevant transformations.
4. Future research and perspectives beyond academia
The project provides a strong scientific foundation for the development of next-generation CO2 conversion technologies. To ensure further uptake and success, several key steps are needed:
• Scalability: Scaling up catalyst synthesis, integrating hybrid electrodes into flow-cell systems, and evaluating long-term operation under industrially relevant conditions.
• Industrial and market engagement: Establishing partnerships with technology developers and industrial stakeholders to assess techno-economic feasibility and application potential.
• IPR and commercialisation support: Evaluating the patentability of the MOF@COF fabrication strategies and exploring licensing or spin-off opportunities.
• Regulatory and standardisation frameworks: Aligning future developments with EU sustainability regulations and standards to facilitate technology adoption.
Overall, ENLIVEN has delivered innovative materials that extend the frontiers of CO2 electroreduction research. By combining scientific excellence with clear pathways for further development, the project contributes meaningfully to the EU’s ambition to build a sustainable, climate-neutral economy.