Ion Dynamics in Porous Carbon Electrodes in Supercapacitors Using in situ Infrared Spectroelectrochemistry
Francis W Richey , Boris Dyatkin , Yury Gogotsi , Yossef A Elabd
Abstract
Electrochemical double layer capacitors (EDLC), or supercapacitors, rely on electrosorption of ions by porous carbon electrodes and offer a higher power and a longer cyclic lifetime compared to batteries. Ionic liquid (IL) electrolytes can broaden the operating voltage window and increase the energy density of EDLCs. Herein, we present direct measurements of ion dynamics of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIm-TFSI) in an operating EDLC with electrodes composed of porous nanosized carbide-derived carbons (CDCs) and non-porous onion-like carbons (OLCs) with the use of in situ infrared spectroelectrochemistry. For CDC electrodes, IL ions (both cations and anions) were directly observed entering and exiting CDC nanopores during charging and discharging of the EDLC.
Conversely, for OLC electrodes, IL ions were observed in close proximity to the OLC surface without any change in the bulk electrolyte concentration during charging and discharging of the EDLC. This provides experimental evidence that charge is stored on the surface of OLCs in OLC EDLCs without long-range ion transport through the bulk electrode. In addition, for CDC EDLCs with mixed electrolytes of IL and propylene carbonate (PC), the IL ions were observed entering and exiting CDC nanopores, while PC entrance into the nanopores was IL concentration dependent.
This work provides direct experimental confirmation of EDLC charging mechanisms that previously were restricted to computational simulations and theories. The experimental measurements presented here also provide deep insights about the molecular level transport of IL ions in EDLC electrodes that will impact the design of electrode materials’ structure for electrical energy storage.
Highlights
We are excited to share that our Carbon-Ukraine (Y-Carbon LLC) company participated in the I2DM Summit and Expo 2025 at Khalifa University in Abu-Dhabi! Huge thanks to Research & Innovation Center for Graphene and 2D Materials (RIC2D) for hosting such a high-level event.It was an incredible opportunity to meet brilliant researchers and innovators working on the next generation of 2D materials. The insights and energy from the summit will definitely drive new ideas in our own development.
Carbon-Ukraine team had the unique opportunity to visit XPANCEO - a Dubai-based deep tech startup company that is developing the first smart contact lenses with AR vision and health monitoring features, working on truly cutting-edge developments.
Our Carbon-Ukraine team (Y-Carbon LLC) are thrilled to start a new RIC2D project MX-Innovation in collaboration with Drexel University Yury Gogotsi and Khalifa University! Amazing lab tours to project collaborators from Khalifa University, great discussions, strong networking, and a wonderful platform for future collaboration.
MXenes potential applications include sensors, wound healing materials, and drug delivery systems. A recent study explored how different synthesis methods affect the safety and performance of MXenes. By comparing etching conditions and intercalation strategies, researchers discovered that fine-tuning the surface chemistry of MXenes plays a crucial role in improving biocompatibility. These results provide practical guidelines for developing safer MXenes and bring the field one step closer to real biomedical applications.
An excellent review highlighting how MXene-based sensors can help tackle one of today’s pressing environmental challenges — heavy metal contamination. Excited to see such impactful work moving the field of environmental monitoring and sensor technology forward!
Carbon-Ukraine team was truly delighted to take part in the kickoff meeting of the ATHENA Project (Advanced Digital Engineering Methods to Design MXene-based Nanocomposites for Electro-Magnetic Interference Shielding in Space), supported by NATO through the Science for Peace and Security Programme.
Exellent news, our joint patent application with Drexel University on highly porous MAX phase precursor for MXene synthesis published. Congratulations and thanks to all team involved!
Our team was very delighted to take part in International Symposium "The MXene Frontier: Transformative Nanomaterials Shaping the Future" – the largest MXene event in Europe this year! 
Last Call! Have you submitted your abstract for IEEE NAP-2025 yet? Join us at the International Symposium on "The MXene Frontier: Transformative Nanomaterials Shaping the Future" – the largest MXene-focused conference in Europe this year! Final Submission Deadline: May 15, 2025. Don’t miss this exclusive opportunity to showcase your research and engage with world leaders in the MXene field!
We are excited to announce the publication of latest review article on MXenes in Healthcare. This comprehensive review explores the groundbreaking role of MXenes—an emerging class of 2D materials—in revolutionizing the fields of medical diagnostics and therapeutics. Read the full article here: https://doi.org/10.1039/D4NR04853A.
Congratulations and thank you to our collaborators from TU Wien and CEST for very interesting work and making it published! In this work, an upscalable electrochemical MXene synthesis is presented. Yields of up to 60% electrochemical MXene (EC-MXene) with no byproducts from a single exfoliation cycle are achieved.
Congratulations to all collaborators with this interesting joint work!