Our recent work on “Competing ion effects and electrolyte optimization for electrochemical lithium extraction from spent lithium iron phosphate battery cathodes” has been featured on the front cover of RSC Energy Advances.
New paper published in ACS Applied Energy Materials on lithium-sulfur batteries. Our collaborative work explored microporous carbon cathodes with carefully tuned pore sizes, tested in both carbonate- and ether-based electrolytes. Our study shows how pore structure and cathode–electrolyte interphase formation impact cycling stability and sulfur utilization. With optimized microporosity, we achieved over 50 mass % sulfur loading and improved performance in carbonate electrolytes. Thanks to all authors (in order of the manuscript) Delvina Tarimo (PhD), Francisco J. Garcia-Soriano, Alen Vizintin, and Christian Prehal.
New paper published on electrochemical lithium-ion battery recycling in Energy Advances. We demonstrate a sustainable, energy-efficient electrochemical route to recover Li⁺ from spent LFP using carbon-coated LFP electrodes, with NaOH-adjusted electrolytes giving the highest efficiency and an average removal capacity of 18 mg Li per 1 g of LFP over 50 cycles. Capacity fades with prolonged cycling (especially with competing Na⁺ and K⁺) highlighting the need to optimize electrolyte conditions and electrode stability while exploring alternative pH control and scalable designs for circular, low-impact battery recycling.
New collaborative paper (Victor H. R. Souza) published in Journal of Power Sources. To support the energy transition, we developed freestanding electrodes combining reduced graphene oxide, polyaniline, and nickel hexacyanoferrate (NiHCF), which is a promising material for aqueous batteries due to its long cycle life and redox-active structure. These rGO/PAni/NiHCF films achieve high specific capacities (up to 83 mAh/g) and integrate both active material and current collector in one, offering a compact and efficient solution for energy storage.
New paper published in Desalination, led by the Gallei Group, on the capture and release of per- and polyfluoroalkyl substances by use of polyelectrolyte metallopolymers.
New paper published in Journal of Hazardous Materials. This collaborative work explores the degradation of microplastics by electrocoagulation via the combination oxidation and flocculation effects.
New paper published in Separation and Purification Technology on “Optimized electrochemical recovery of lithium-ions from spent battery cells using carbon-coated lithium iron phosphate”. We optimized a system based on carbon-coated lithium iron phosphate electrodes. The electrodes selectively extract lithium ions from complex leaching solutions derived from real LCO (LiCoO₂) cathode materials. Over the course of 300 cycles, we observed an average lithium uptake capacity of about 11 mg of Li-ions per 1 gram of active material per cycle. We also demonstrated excellent selectivity toward lithium over competing ions like calcium and cobalt, which is critical in real-world leachates. Our optimized electrode materials and cycling strategies improve both the performance and lifetime of the electrochemical recovery system.
We acknowlege the contributions of all co-authors (Stefanie Arnold, Lei Wang, Dr Rudi Mertens, and Sascha Wieczorek).
New paper published in Electrochimica Acta on “Transparent polyaniline/MXene thin films supercapacitors”. In this collaborative work, we developed transparent, nanostructured films combining MXene Ti3C2Tx and polyaniline for miniaturized energy storage devices. The films show promising electrochemical performance and stability, opening avenues for transparent supercapacitor applications. Co-authors: Ariane Schmidt, Samantha Husmann, and Aldo J.G. Zarbin.
Thrilled to see our 2023 paper “The many deaths of supercapacitors: Degradation, aging, and performance fading” is among the 10 most cited articles of 2023 of the high-impact factor journal Advanced Energy Materials.
New paper published in ACS Applied Polymer Materials. This joint work with Markus Gallei from Saarland University has developed smart core–shell particles with imidazole-functionalized shells that respond to acidic solutions and hydrophobic anions, forming viscoelastic opal films with tunable structural colors. These films serve as affordable optical sensors, changing color in response to environmental stimuli, with potential applications in life sciences, environmental monitoring, and electrochemistry.
New paper published on synthesis and self-assembly of pore-forming three-arm amphiphilic block copolymers in Macromolecular Rapid Communications from the collaboration with Markus Gallei.
New paper in Energy & Environmental Materials: Dry Electrode Processing for Free-Standing Supercapacitor Electrodes with Longer Life, Higher Volumetric Outputs, and Reduced Environmental Impact.
Our research explores the benefits of dry electrode processing for supercapacitors. As one of the pioneering energy storage systems to adopt dry electrode processing (e.g., through [formerly] Maxwell), supercapacitors have shown significant advancements in this area. Our study follows up with this processing technology and demonstrates notable improvements in electrode lifespan, volumetric energy density, and environmental sustainability by utilizing dry processing techniques. By bypassing conventional solvent-based methods, we achieved a 28% increase in energy density and a reduction in manufacturing-related CO2 emissions, while also extending the lifespan of supercapacitors across various electrolytes, including organic, ionic liquids, and quasi-solid state.
In the broader context, this research contributes to the ongoing efforts to enhance energy storage technologies. Supercapacitors are crucial for bridging the gap between batteries and capacitors, offering rapid charge/discharge capabilities and long cycle life. The adoption of dry electrode processing can advance their sustainability and, at the same time, yield a better performance per the more intricate particle-particle contact and ability to obtain even ultra-thick electrodes (in our work: up to 700 µm).
Team Jena: Marius Hermesdorf, Desirée Leistenschneider; Team Saarbrücken: Emmanuel Pameté, Jean Gustavo De Andrade Ruthes, Anna Seltmann, Delvina Tarimo (PhD).
Making an electrode is art and science: The relevance of electrode preparation optimization and potential window maximization for high-rate lithium-ion batteries. Our new paper in Advanced Energy and Sustainability Research optimizes lithium titanate (LTO) anodes for lithium-ion batteries. By tweaking the dry and wet mixing processes during electrode fabrication, we achieved remarkable improvements in capacity retention, especially at high charge rates. Employing an extended potential window of 0.01-3.00 V vs Li+/Li, a high capacity of about 290 mAh/g at 0.1 A/g was obtained. Specifically, using the best-performing electrode processing in our work, we obtained a capacity of 232 mAh/g at 1C with a capacity retention of 80% after 300 cycles at a rate of 34C (68% after 1000 cycles). These results highlight the importance of control over particle dispersion in maximizing electrode performance.
This work underscores the potential of LTO as a durable and safe option for applications where high power and long cycle life are critical, such as electric vehicles and grid storage. By reducing solvent usage by up to 50%, our study shows the potential of cost and material savings per optimized processing.
Many thanks to all authors: Amir Haghipour, Stefanie Arnold, Jonas Oehm, Dominik Schmidt, Lola Gonzalez-Garcia, Dr. Hitoshi Nakamura, Tobias Kraus, and Volker Knoblauch
New paper published on “Multi-scale circuit model bridges molecular modeling and experimental measurements of conductive metal-organic framework supercapacitors” in Physical Chemistry Chemical Physics.
We are excited to announce the publication of our latest collaborative perspective paper in Advanced Functional Materials, where we explore the role of MXene-enabled technologies in shaping the cities of tomorrow.
With over 60% of the world’s population now living in urban areas, the need for smart urbanization has never been greater. The concept of the smart city envisions a self-sufficient, responsive, and interactive urban environment—one that seamlessly integrates technology to enhance the well-being of its citizens. MXenes, a class of tunable 2D nanomaterials, are emerging as a key enabler of this transformation.
In this perspective, we outline how MXenes can drive sustainable urban development by advancing:
Self-sufficient and adaptive buildings that optimize energy, water, and air usage.
Next-generation IoT and telemedicine applications, overcoming technological barriers with their unique multifunctional properties. A roadmap for practical MXene integration, demonstrating their feasibility in real-world smart city infrastructures.
- Self-sufficient and adaptive buildings that optimize energy, water, and air usage.
- Next-generation IoT and telemedicine applications, overcoming technological barriers with their unique multifunctional properties.
- A roadmap for practical MXene integration, demonstrating their feasibility in real-world smart city infrastructures.
Many thanks to Michael Naguib and Agnieszka M. Jastrzębska for this interesting collaboration.
New open access paper published in ACS Applied Materials & Interfaces on “Understanding Rate and Capacity Limitations in Li-S Batteries Based on Solid-State Sulfur Conversion in Confinement”. This study explores how solid-state sulfur conversion within carbon nanopores enhances the performance of lithium-sulfur batteries. Key parameters relate to cathode-electrolyte interphase (CEI) formation, pore size, and material design.
Key findings from our study:
- Nanopore engineering: Small nanopores (<0.8 nm) promote efficient CEI formation, improving charge transfer and enabling solid-state sulfur conversion without polysulfide dissolution.
- Rate limitation insights: Charge transfer between sulfur and carbon dominates rate limitations, particularly during charging, while lithium-ion transport plays a secondary role.
- Material utilization: Optimized sulfur-to-carbon ratio maximizes the capacity by balancing pore filling and reaction kinetics.
- Advanced methodologies: Techniques like operando SANS and XRD provide evidence for the stability of solid-state conversion processes and the amorphous nature of sulfur products within nanopores.
This work is an outcome of the Slovenian-Swiss-Austrian-German ALISA project (Advanced Lithium-Sulfur batteries with ultramicroporous carbons), supported by the European Commission Horizon 2020 program and various national funding agencies (including Bundesministerium für Bildung und Forschung). It contributes to the broader effort of advancing sustainable and high-energy-density battery systems, aligning with global clean energy goals.
Thank you for the great collaboration Ayça Şenol Güngör, Jean-Marc von Mentlen, Jean Gustavo De Andrade Ruthes, Francisco J. García-Soriano, Sara Drvarič Talian, Lionel Porcar, Alen Vizintin, Vanessa Wood, and Christian Prehal
Our latest research in Energy & Environmental Science explores an eco-friendly, high-performance lithium-ion anode made from self-assembled organic nanowires. By evaporating water on a copper current collector, we achieved a nanowire network without harmful solvents, enhancing lithium-ion diffusion and storage capabilities. The result? The self-assembled organic nanowire anode delivers a remarkable lithium storage capacity of up to 1888 mA h/g at 0.1 A/g, retaining 508 mA h/g even at a high current rate of 10 A/g. In lithium-ion capacitors, it achieves a specific energy of 156 W h/kg at 0.34 kW/kg and maintains 60.2 W h/kg at 19.4 kW/kg, outperforming many state-of-the-art systems.
This Czech-German research collaboration was carried out by Ievgen Obraztsov, Rostislav Langer, Jean G. A. Ruthes, Volker Presser, Michal Otyepka, Radek Zboril, and Aristides Bakandritsos.
Our new paper, Electrochemical recycling of lithium-ion batteries: Advancements and future directions, is now available online at the Wiley journal EcoMat. Our review provides a perspective of different recycling techniques currently used for lithium-ion batteries. We begin by reviewing the more established pyrometallurgical and hydrometallurgical methods, which have been widely adopted in industrial applications. These methods, while effective, often involve high energy consumption and the use of chemical reagents, raising concerns about their long-term sustainability.
Building on this foundation, we focus on emerging electrochemical approaches, which offer a more sustainable alternative by using electricity to recover valuable metals like lithium, cobalt, and nickel. This method reduces the need for harmful chemicals and promises lower energy demands, especially when powered by renewable energy sources. However, despite these advantages, electrochemical recycling is not without its challenges. Our paper critically examines key issues such as scalability and selectivity. We emphasize the need for further research to address these obstacles and unlock the full potential of electrochemical recycling to improve metal recovery efficiency while minimizing waste and environmental impact.
In the broader context of the energy transition, efficient battery recycling is becoming increasingly important. As demand for electric vehicles and renewable energy storage rises, ensuring the sustainable recovery of metals like lithium, cobalt, and nickel is crucial. While electrochemical methods are promising, significant technical challenges remain to be addressed before these processes can be widely adopted. We believe our work contributes to a deeper understanding of the current landscape and offers insights into future directions.
New paper published on cation separation during flow electrode capacitive deionization in Desalination. This work is about improving water treatment and resource recovery through selective ion removal using flow electrode capacitive deionization (FCDI). We explore separating specific cations like calcium and magnesium from multi-ion solutions, helping to optimize water desalination processes. Our data show that while the overall ion separation order follows a universal order, the kinetics (down to full ion depletion) can be adjusted as a function of carbon mass loading, presence or absence of conductive additive, and flow rate.
New paper published in Nature Communication. This highly collaborative work (spearheaded by Dr. Gündoğ Yücesan) presents polyphosphonate covalent organic frameworks (COFs) constructed via P-O-P linkages, synthesized through a one-step condensation reaction. This process involves heating a hydrogen-bonded precursor made from phenylphosphonic acid and porphyrin, without chemical reagents. At temperatures above 210 °C, the COF transforms into an amorphous microporous structure due to P-O-P bond oligomerization, confirmed by 31P NMR. The COF shows excellent stability in water, water vapor, and in 0.5 M Na2SO4 electrolyte, filling a gap in COF literature for stable, microporous materials. Additionally, its narrow pores effectively capture CO2, with a sustainable synthesis route.
