Periodic Reporting for period 1 - PARIS (Porous poly(ionic liquid)s for CO2 capture and simultaneous conversion under ambient conditions)
Reporting period: 2022-12-01 to 2025-05-31
CO2 capture, storage and utilization is judged critical to mitigate the rapid rise in the atmospheric CO2 concentration. A key problem is the gigantic mass of CO2 emitted, which asks for robust, efficient and economically viable approaches that are currently missing and limited by the lack of suitable materials. To break through this barrier, I aim to develop metal-free dual-function porous poly(ionic liquid)s (DPPs) to capture and convert CO2 under ambient conditions into cyclic carbonates with high efficiency, and to apply them in model reactors for cost-effective processing of CO2.
Poly(ionic liquid)s (PILs) are innovative ionic materials, in which ionic liquids (ILs) are covalently joined by a macromolecular backbone. ILs are known CO2-philes, and IL-derived PILs are naturally in favour of CO2 sorption, while their ions can be tailor-made for catalytic CO2 transformation. Such dual-function as sorbent and catalyst is the intrinsic merit of PILs to address the CO2 challenge, but unfortunately has been long impeded by the mismatched chemical structures in each function. Our preliminary work proved that the newly emerging 1,2,4-triazolium PILs were catalytic active and drastically more CO2-philic than common polyimidazoliums, and are believed as the game-changer materials. We envision that by structuring chemically tailor-made 1,2,4-triazolium PILs into highly porous materials, they will be able to capture and convert CO2 under ambient conditions. This ground-breaking materials concept will circumvent the complicated, harsh conditions for CO2 fixation, and cut the cost to an affordably low level.
This project will radically advance scientific knowledge and technology to fixate and convert CO2 at scale into value-added chemicals that further reduces the consumption of fossil resources. Its outcome will expedite the research in PILs and dual-function materials to revolutionize the CCU routes and equip us with powerful materials tools to mitigate the global CO2 rise.
Poly(ionic liquid)s (PILs) are innovative ionic materials, in which ionic liquids (ILs) are covalently joined by a macromolecular backbone. ILs are known CO2-philes, and IL-derived PILs are naturally in favour of CO2 sorption, while their ions can be tailor-made for catalytic CO2 transformation. Such dual-function as sorbent and catalyst is the intrinsic merit of PILs to address the CO2 challenge, but unfortunately has been long impeded by the mismatched chemical structures in each function. Our preliminary work proved that the newly emerging 1,2,4-triazolium PILs were catalytic active and drastically more CO2-philic than common polyimidazoliums, and are believed as the game-changer materials. We envision that by structuring chemically tailor-made 1,2,4-triazolium PILs into highly porous materials, they will be able to capture and convert CO2 under ambient conditions. This ground-breaking materials concept will circumvent the complicated, harsh conditions for CO2 fixation, and cut the cost to an affordably low level.
This project will radically advance scientific knowledge and technology to fixate and convert CO2 at scale into value-added chemicals that further reduces the consumption of fossil resources. Its outcome will expedite the research in PILs and dual-function materials to revolutionize the CCU routes and equip us with powerful materials tools to mitigate the global CO2 rise.
Our major achievements in the initial two years lies in the smooth build-up of the ERC team, and the exploratory activities on design and synthesis of CO2 sorbents and catalysts for CO2 conversion.
Above all, our team has succeeded in synthesizing various dual-functional porous polymers with high specific surface area (SBET) up to 625 m2/g and with high pore volume up to 1.20 cm3/g, and the team is continuing to push forward the SBET above 800 m2/g and a pore volume above 2.5 cm3/g. In addition, the team has produced aminated porous polymeric systems with the sorption capacity of ca. 10 wt%, which is far more than 5 wt%, as originally planned in the proposal. The CO2 sorption process is rather quick and could reach > 90% of total uptake on the minute scale. When tested in the cycloaddition reaction of CO2 onto epoxide catalyzed by dual-functional porous polymers, a high yield of ≥ 95% and selectivity ≥ 95% have been realized, and our current efforts focus on the improvement of the reaction kinetics and durability, and the lowering-down of reaction temperature. A model reactor to achieve cost-effective CO2 capture and conversion is ongoing in the lab.
Main achievements include:
1) 21 peer-reviewed journal articles from the PARIS project.
2) Successful synthesis of more than 5 different porous polymers for CO2 capture and conversion.
3) Verification of the proof-of-the-concept of simultaneous CO2 capture and conversion.
Above all, our team has succeeded in synthesizing various dual-functional porous polymers with high specific surface area (SBET) up to 625 m2/g and with high pore volume up to 1.20 cm3/g, and the team is continuing to push forward the SBET above 800 m2/g and a pore volume above 2.5 cm3/g. In addition, the team has produced aminated porous polymeric systems with the sorption capacity of ca. 10 wt%, which is far more than 5 wt%, as originally planned in the proposal. The CO2 sorption process is rather quick and could reach > 90% of total uptake on the minute scale. When tested in the cycloaddition reaction of CO2 onto epoxide catalyzed by dual-functional porous polymers, a high yield of ≥ 95% and selectivity ≥ 95% have been realized, and our current efforts focus on the improvement of the reaction kinetics and durability, and the lowering-down of reaction temperature. A model reactor to achieve cost-effective CO2 capture and conversion is ongoing in the lab.
Main achievements include:
1) 21 peer-reviewed journal articles from the PARIS project.
2) Successful synthesis of more than 5 different porous polymers for CO2 capture and conversion.
3) Verification of the proof-of-the-concept of simultaneous CO2 capture and conversion.
We list two results beyond the state of the arts
i) In collaboration for the synthesis of α-alkylidene cyclic carbonates (αCCs), we utilized a refined, homogeneous silver–carbene–organobase catalytic system to optimize batch conditions to achieve, for the first time, complete conversion of tertiary propargylic alcohols within minutes instead of hours. This success allows for fast quantitative conversion of αCCs at a scale of 100+ g per day. The poly(1,2,4-triazoliuym) used in the PARIS project is a precursor of polycarbene and may serve this reaction similarly. (Green Chem., 2025,27, 722-730. https://doi.org/10.1039/D4GC05716C(opens in new window))
ii) Our recent paper on “Ionic Conjugated Microporous Polymers for Cycloaddition of Carbon Dioxide to Epoxides” ([Macromol. Mater. Eng. 2024, 309, 2300218] https://doi.org/10.1002/mame.202300218(opens in new window)). This paper marks an important advance of synthesis of porous imidazolium-based poly(ionic liquid)s in one-step in an aqueous solution under 100 oC. In comparison to the complex procedure that we have previously planned for solvothermal synthesis of porous poly(ionic liquid). Our outcome in this paper demonstrates an alternative greener route to produce porous ionic polymer networks for simultaneous CO2 capture and conversion.
i) In collaboration for the synthesis of α-alkylidene cyclic carbonates (αCCs), we utilized a refined, homogeneous silver–carbene–organobase catalytic system to optimize batch conditions to achieve, for the first time, complete conversion of tertiary propargylic alcohols within minutes instead of hours. This success allows for fast quantitative conversion of αCCs at a scale of 100+ g per day. The poly(1,2,4-triazoliuym) used in the PARIS project is a precursor of polycarbene and may serve this reaction similarly. (Green Chem., 2025,27, 722-730. https://doi.org/10.1039/D4GC05716C(opens in new window))
ii) Our recent paper on “Ionic Conjugated Microporous Polymers for Cycloaddition of Carbon Dioxide to Epoxides” ([Macromol. Mater. Eng. 2024, 309, 2300218] https://doi.org/10.1002/mame.202300218(opens in new window)). This paper marks an important advance of synthesis of porous imidazolium-based poly(ionic liquid)s in one-step in an aqueous solution under 100 oC. In comparison to the complex procedure that we have previously planned for solvothermal synthesis of porous poly(ionic liquid). Our outcome in this paper demonstrates an alternative greener route to produce porous ionic polymer networks for simultaneous CO2 capture and conversion.