New paper published in Macromolecules on surface-initiated living anionic polymerization of functional methacrylates from the surface of organic particles.

Very happy to announce that Jean Gustavo takes up the mantle of responsibility and will support the continued growth of our team in the role as Deputy Group Leader! We are looking forward to working with him in his new role to push forward our research at the energy / water / sustainability nexus.

Light bulb from water splash

New paper published in ACS Nano. Our work explores horn-like pore entrance geometries that boost the overall charging dynamics and charge storage of nanoporous supercapacitors. This work was in collaboration with Guang Feng (HUST).

New article published in Journal of Materials Chemistry A on high performance Mo(C,N,O)x Li-ion battery anodes. Using a continuous wet-chemical process process called a microjet reactor, we combined ammonium heptamolybdate with para-phenylenediamine, tweaking the mix to get just the right results. After applying thermal annealing, we obtained Mo(C,N,O)x with stacking defects embedded in a carbonaceous matrix. Depending on the synthesis and annealing parameters, different morphologies and phases were observed. The best of our materials yielded a high capacity of 933 mAh/g after 500 cycles! 🔋

933 mAh/g after 500 cycles… so the initial capacity must have been higher? Actually, no! On the contrary, we s tarted with about 500 mAh/g, went down a bit and then almost doubled the capacity between the 100th and 500th galvanostatic charge/discharge cycle. This has to do with the “magic of molybdenum”, as we had seen similar effects of self-activation before.🔬

Big shoutout to Mana Abdirahman Mohamed, Oliver Janka, Jörg Schmauch, and Guido Kickelbick from Universität des Saarlandes for the exciting project . 🤝 Kudos to Stefanie Arnold for her patience with this project and her excellent expertise! 🌟 And a special thanks to the Leibniz Institute for Plasma Science and Technology (INP Greifswald) e.V. (Antje Quade) for X-ray photoelectron spectroscopy. 🙌

New review article published in Advanced Energy Materials on the degradation of supercapacitors, as featured as “Editor’s Choice” and on the front cover.

Our review discusses the significance of monitoring methods and strategies for tracking the performance degradation of EDLCs and pseudocapacitors, employing a range of cutting-edge techniques such as electrochemical methods and in situ and ex situ analyses. These methods enable researchers to better understand the underlying mechanisms behind supercapacitor aging.

We also explore the intricate interplay of electrode materials, electrolytes, and other critical system aspects, including pore blocking, electrode compositions, functional groups, and corrosion of current collectors. When we understand these factors, we can pave the way for enhanced supercapacitor designs and materials that offer prolonged lifespan and improved performance. Moreover, we also examine the impact of aging from an industrial application standpoint, providing valuable insights into the real-world scenarios. And finally, we highlight future directions and challenges, including the development of innovative materials and advanced monitoring methods, to combat performance degradation effectively.

Team INM-Leibniz Institute for New MaterialsEmmanuel PametéVolker Presser
Team Friedrich Schiller University JenaLukas KöpsFabian KrethAndrea Balducci
Skeleton TechnologiesSebastian Pohlmann
Helmholtz Institute Ulm (HIU)Alberto Varzi
Nantes UniversitéThierry Brousse

New paper published in Nano Research. Heavy metal pollution is a major environmental problem to the environment and human health. Adsorption is an effective approach with a straightforward process, adaptability to a wide range of water concentrations, and high selectivity. But commonly, the materials are designed for a one-time-use and discarded after they have reached their uptake capacity.

Electrochemistry is a promising way to re-use materials by simple charge/discharge cycling. We demonstrated electrochemically enhanced selective lead removal with FeOOH. FeOOH is an environmentally friendly and cost-effective sorbent. And it is conveniently available on large scale. Our work demonstrates the feasibility of regenerating FeOOH by charge and provides a new approach for recycling and upcycling FeOOH sorbent.

Our recent study investigated the selectivity of FeOOH in a mixed solution of Co2+, Ni2+, and Pb2+ and proposed to enhance the capacity and regenerate FeOOH by using external charges. Our results demonstrated that FeOOH showed superior selectivity towards Pb2+ compared to Co2+ and Ni2+, with a purity of 97±3% in the extracts. The high selectivity is attributed to the lower activation energy for Pb2+ sorption. The system also exhibited a Pb2+ uptake capacity of 37.4 mg/g with high selectivity when using industrially exhausted granular ferric hydroxide as the electrode material.

New paper published on iron vanadate derived from Prussian Blue analog for Lithium-ion batteries in Sustainable Energy & Fuels. This marks our latest work on derivatization strategies to turn Prussian Blue Analogs (PBAs) into mixed metal oxide materials for battery applications 🔋

🔹We used PBAs as they offer a very high tunability and ease of synthesis.
🔹We successfully achieved homogeneous iron vanadate derivatization using an energy-efficient infrared furnace with CO2 gas.
🔹We entangled the active material with carbon nanotubes to generate binder-free, free-standing electrodes for direct use as electrodes.
🔹We stabilized the electrochemical performance reaching a 400 mAh/g capacity at a specific current of 250 mA/g after 150 cycles, maintaining a Coulombic efficiency of 99.2% in a potential range of 0.01-3.5 V vs. Li/Li+.
🔹The choice of electrolyte matters (of course) also, with a better performance in Li-TFSI in carbonate electrolyte compared to Li-PF6.

For an in-depth understanding of our methodology and findings, I encourage you to read the full paper where we delve deep into the role of different surfactants and the optimization of various parameters for a stable electrochemical performance.

New paper published in Small on Cu/V-Organophosphonates. In this collaborative work, we report a layered redox-active, antiferromagnetic metal organic semiconductor crystals with the chemical formula [Cu(H2O)2V(µ-O)(PPA)2] (where PPA is phenylphosphonate). 

New paper published on hydrogel-based flexible energy storage in Advanced Materials Interfaces. Our study showcases a novel electrolyte system that stands out due to its flexibility, electroactivity, and improved sustainability.
We initiated our research by electropolymerizing polypyrrole (PPy) nanotubes in graphite-thread electrodes, utilizing methyl orange templates in an acidic medium. This process successfully enhanced the conductivity, while maintaining the flexibility of the electrodes, a crucial component in developing versatile energy storage systems. We built flexible devices using hydrogel as an electrolyte prepared from poly(vinyl alcohol) (PVA)/sodium alginate (SA). This hydrogel was obtained through freeze-thawing and swelling with ionic solutions. The result was a homogenous and porous hydrogel matrix, demonstrating high conductivity of 3.6 mS/cm as-prepared and the ability of self-healing.

What sets this material apart is its adaptability. The material’s electrochemical and mechanical properties depend on the swollen electrolyte used, allowing its integration with the modified graphite-thread electrodes. This flexibility led us to develop a quasi-solid electrochemical energy storage device, with a specific capacitance value of 66 F/g at 0.5 A/g. The choice of less environmentally friendly acid electrolyte HNO3 yielded a higher capacitance in the range of 100 F/g. These attributes relied on the liquid phase in the hydrogel matrix produced from biodegradable polymers.

We thank our collaborators who were instrumental in this research project. Special acknowledgment to our esteemed colleagues from the Departamento de Química, Universidade Federal do Paraná in Brazil: Andrei Elias Deller, Izabel C. Riegel-Vidotti, and Marcio Vidotti. On our team, we are grateful for the contributions of Ph.D. student Jean Gustavo De Andrade Ruthes, our postdoc and Humboldt-Fellow Emmanuel Pameté.

Volker Presser gives an online seminar with the title “Electrochemical Lithium-Ion Extraction” at DIFFER (Dutch Institute for Fundamental Energy Research).

The progressing electrification of water remediation: review article on electrosorption of organic compounds in Chemical Engineering Journal.
I am happy to see now-online our latest review paper, which summarizes the science and technology of electrosorption of organic compounds (EOC). Traditional methods of water treatment, such as adsorption, encounter limitations when it comes to effectively removing ionic and hydrophilic organic contaminants. Moreover, the lack of on-site regeneration techniques further hinders the efficiency of these methods. EOC not only enhances the adsorption performance but also enables green electricity-assisted regeneration of the adsorbent.
Over the past decades, the field of EOC has witnessed exponential growth in research studies. Many examples demonstrate that the application of electrical potentials can remarkably enhance the adsorption affinity, capacity, and kinetics of conductive carbon adsorbents. However, it remains unclear whether these effects are specific to certain compound classes or universally applicable, and the optimal criteria for designing EOC processes remain elusive.
In our research, we conducted a critical evaluation of the current state of the art in EOC, with a primary focus on active control of adsorption and desorption processes and their effects on both ionic and neutral organic compounds. By thoroughly considering compound speciation and surface chemistry of electrode materials, we gained mechanistic insights into the EOC process and highlighted the differences between electrosorption of inorganic and organic compounds.
We have also proposed insightful performance parameters and provided clear definitions to unify the rapidly expanding research in the EOC field. By doing so, we aim to establish a foundation for consistent analysis and evaluation of EOC techniques. Furthermore, we discuss potential application scenarios and outline future research directions to guide the development of this exciting technology. EOS, thereby, is not a one-size-fits-all solution for removing contaminants. However, it offers a valuable tool, particularly for tackling the challenges posed by hydrophilic and ionic organic contaminants, which often prove difficult for conventional adsorption processes.
Thanks to the great team of scientists authoring the work from the Helmholtz Centre for Environmental Research (UFZ): Navid SaeidiFalk Harnisch, Franz-Dieter Kopinke, Anett Georgi

We are very happy that Delvina Tarimo (PhD) has been awarded a research fellowship by the Alexander von Humboldt Foundation! Delvina will be carrying out work on nanoconfinement and lithium-sulfur batteries. Congratulations, Delvina, and thanks for choosing the INM-Leibniz Institute for New Materials and our team for your research!

Work of our group has been presented at the 6th International Conference on Battery Deionization & Electrochemical Separation (BDI&E 2023). Former group member, Prof. Choonsoo Kim, presented joint work on “Redox-mediated Electrodialysis for Valorization of Tetramethylammonium hydroxide (TMAH) from Semiconductor Wastewater”. Volker Presser gave an online talk on “Continuous and intermittent direct electrochemical lithium extraction”.

Stefanie Arnold has successfully defended her Ph.D. thesis “Next generation (hybrid) battery materials at the water/energy/recycling nexus”. Congratulations, Dr. Arnold!

Jean Ruthes and Volker Presser present at the 2nd Franco-German Summer Workshop on High Power Devices in Nantes (France).

Volker speaks about “MXene and hybrid electrodes for high performance energy storage” on the 21st of June.

Jean speaks about “Hydrogel-based flexible energy storage using electrodes based on polypyrrole and carbon threads” on the 23rd of June.

Volker Presser gives an online talk entitled “Electrochemical Desalination” as part of the Nanohubs Program of the Department of Science and Technology in the Philippines within the Theme “Empowering Young Filipino Researchers for an Emerging Technology Ready Philippines”.

New work published in Carbon in collaboration with Prof. Choonsoo Kim. In our research, we explore the impact of different carbon types on desalination capacity and rate. We exemplify the impact of conventional carbon black, nanoscaled carbon onions, and micro-mesoporous carbons. In the early cycles, we observed that using AC electrodes without additives resulted in a higher desalination capacity, reaching approximately 10 mg/g. However, there was a trade-off: the desalination rate was slightly lower. It turns out that larger AC particles limited the transportation of ions within the electrode due to the increased diffusion path length.

By incorporating small and less porous additives, we achieved the highest desalination rate (20 μg/g/s) as the additive particles reduced the ion diffusion path length by increasing size dispersion, thus enhancing overall ion transport and desalination rates.

Welcome new Postdoc Jian Zhou, who will be working on electrochemical desalination with us.

Expanding the 2D flatlands: toward MBene Li- and Na-ion batteries 🔋

In our ongoing research to identify sustainable technological alternatives 🌱, we have explored the potential of layered boride materials (MoAlB and Mo2AlB2) for their use in Lithium-ion and Sodium-ion batteries (LIBs and SIBs) 🔬. Great to see our Open Access paper now appeared in print in Small Methods! 🖨️

Some key findings from the paper include:
👉Unlike MXene, no HF is needed for the 3D-to-2D etching reaction🧪
👉Sodium hydroxide treatment applied to MoAlB results in a porous morphology 🍯, leading to higher specific capacities than its original form
👉Mo2AlB2 showcases a more promising specific capacity compared to MoAlB for LIBs, registering a specific capacity of 593 mAh/g after 500 cycles at 200 mA/g ⚡
👉When it comes to SIBs, Mo2AlB2 demonstrated a specific capacity of 150 mA/g at 20 mA/g 📊.
These findings underscore the potential of layered borides as an interesting electrode materials for both LIBs and SIBs, and illuminate 🔦 the significance of surface redox reactions in Li storage mechanisms.

A sincere thank you 🙏 to our amazing partners for their invaluable contributions and collaboration.

Tulane University:
Ahmad Majed
Chukwudi Nwaokorie
Karamullah Eisawi
Audrey Buck
Matthew Montemore
Michael Naguib

INM-Leibniz Institute for New Materials:
Mohammad Torkamanzadeh
Volker Presser

Berkeley Lab:
Chaochao Dun
Jeff Urban

New paper published in a special issue of Energy Technology on battery research ontology. This work offers a logical framework that seamlessly integrates with digital architecture, enabling efficient visualization, correlation, and prediction capabilities in battery production, research, and development.

The ontology employs a predetermined terminology to specify materials and processes, establishing a chain of unit processes that connect raw materials to the final products of battery cell production. Moreover, it facilitates the attachment of analytical methods, known as characterization methods, to the relevant items. To ensure its suitability for both industrial-scale and laboratory-scale data generation and implementation, extensive workshops and interviews with battery materials and production process experts were conducted during its development.

The ontology encompasses the identification and definition of raw materials and intermediate products across all production steps, ultimately leading to the creation of the battery cell. Standard materials and process chains serve as the foundation for defining steps and items using commonly used terms. Furthermore, the research explores alternative structures and the integration of the ontology with existing ontologies.