Foto: Annegret Günther / FSU Jena
Prof. Dr. Philipp Adelhelm
Philipp Adelhelm (geb. 1978 in Waiblingen) studierte Werkstoffwissenschaften an der Universität Stuttgart / Max-Planck-Institut für Metallforschung mit Auslandsaufenthalten in Auckland (Neuseeland) und Stockholm (Schweden). Von 2005 bis 2007 arbeitete er am Max-Planck-Institut für Kolloid- und Grenzflächenforschung in Potsdam (Prof. Antonietti, Prof. Smarsly) auf dem Forschungsgebiet "poröse Kohlenstoffmaterialien" und wurde dort 2007 an der Universität in physikalischer Chemie promoviert. Es folgten zwei Jahre als Postdoktorand am Debye Institute for Nanomaterials Science (Group of Inorganic Chemistry and Catalysis, Prof. de Jongh, Prof. de Jong,) mit Arbeiten zur Wasserstoffspeicherung in nanostrukturierten Metallhydriden. Ende 2009 schloss er sich als Nachwuchsgruppenleiter der Arbeitsgruppe von Prof. Jürgen Janek am Physikalisch-Chemischen Institut der Justus-Liebig-Universität Gießen an und forschte an Materialien für elektrochemische Energiespeicher. Seit April 2015 ist er W3-Professor am Institut für Technische Chemie und Umweltchemie an der Friedrich-Schiller-Universität Jena.
Energy storage materials / Electrochemistry
Philipp Adelhelm is a materials scientist and received his education at the University of Stuttgart and the Max-Planck-Institute for Metals Research. After graduation in 2004, he joined the group of Prof. Markus Antonietti at the Max-Planck-Institute of Colloids and Interfaces in Potsdam, Germany, and worked on the synthesis and characterization of carbon materials with tailored porosity. He received his PhD in physical chemistry in 2007 and continued his academic career as a post doc at the Debye Institute of Nanomaterials Science in Utrecht, The Netherlands, under supervision of Prof. Petra de Jongh and Prof. Krijn de Jong studying sodium and magnesium based hydrogen storage materials. During his stay as group leader at the Justus-Liebig-University Giessen, Germany (Institute of Physical Chemistry, RG Prof. Juergen Janek) his research aimed at exploring the cell chemistry of sodium based battery systems with the focus on carbon materials, conversion reactions, sodium/air and low temperature sodium/sulfur systems. On 1st of April 2015, he was appointed professor at the Institute for technical chemistry and environmental chemistry (ITUC) at the Friedrich-Schiller-University Jena. He is also part of the newly established Jena Center for Energy and Environmental Chemistry (CEEC) that was inaugurated in fall 2015. He is also member of the directorate of the Working group „Chemistry and Energy“ of the GDCh (www.gdch.de/chemie-und-energie)
- Carbon materials (synthesis, modification and characterization)
- Lithium-ion and sodium-ion batteries, next generation battery systems
- Thin film materials
Current research projects are supported by the Friedrich-Schiller-University Jena, the state of Thuringia (Pro Excellence program), the German Research Foundation DFG, the Sino-German Center CDZ and the German Federal Ministry of Education and Research BMBF.
Interested? – Feel free to contact us for more information
Selected research projects and publications:
Sodium as alternativ to Lithium?
Lithium-ion and sodium-ion batteries share many common features but also many surprising differences. Understanding the influence of ion size on the cell chemistry of batteries is an intriguing research field. Moreover, the abundance of sodium is highly attractive for developing low cost, large scale energy stores.
P. Adelhelm; Alternative
Natrium, Nachrichten aus der Chemie 62, 2014 (Perspective)
Graphite for sodium-ion batteries
Although being the standard anode material in lithium-ion batteries (LIBs), graphite so far is considered to fail application in sodium-ion batteries (NIBs) because the Na-C system lacks suitable binary intercalation compounds. Here we show that this limitation can be circumvented by using co-intercalation phenomena in a diglyme-based electrolyte. Highlights of the electrode reaction are its high energy efficiency, the small irreversible loss during the first cycle, and a superior cycle life with capacities close to 100 mAh g−1 for 1000 cycles and coulomb efficiencies >99.87 %.
and Adelhelm P; Use of Graphite as a
Highly Reversible Electrode with Superior Cycle Life for Sodium-Ion Batteries
by Making Use of Co-Intercalation Phenomena, Angew. Chemie Int. Ed. 53, 2014
The sodium superoxide battery
In the search for room-temperature batteries with high energy densities, rechargeable metal–air (more precisely metal–oxygen) batteries are considered as particularly attractive owing to the simplicity of the underlying cell reaction at first glance. Here we report on a Na–O2 cell reversibly discharging/charging at very low overpotentials (< 200 mV) and current densities as high as 0.2 mA cm−2 using a pure carbon cathode without an added catalyst. Crystalline sodium superoxide (NaO2) forms in a one-electron transfer step as a solid discharge product. This work demonstrates that substitution of lithium by sodium may offer an unexpected route towards rechargeable metal–air batteries.
Hartmann P, Bender CL, Vračar M, Dürr AK, Garsuch A, Janek J, Adelhelm P, A rechargeable room-temperature sodium superoxide (NaO2) battery, Nature Materials 12, 2013
Bender CL, Hartmann P, Vracar M, Adelhelm P, Janek J On the Thermodynamics, the Role of the Carbon Cathode, and the Cycle Life of the Sodium Superoxide (NaO2) Battery, Adv. Energy Mater. 4, 2014Bender CL, Schroeder D, Pinedo R, Adelhelm P, Janek J, One- or Two-Electron Transfer? The Ambiguous Nature of the Discharge Products in Sodium–Oxygen Batteries, Angewandte Chemie Int. Ed., 2016
Room-temperature sodium-sulfur batteries
The cell chemistry of sodium/sulfur cells operating at room temperature (RT-Na/S cells) is being studied electrochemically and structurally. We show by means of X-ray photoelectron spectroscopy that the cell reaction is incomplete but prove that the end members of the cell reaction (S and Na2S) form among the expected polysulfide species Na2Sx. The sulfur utilization can be improved by employing a solid electrolyte membrane (beta″-alumina) that prevents the diffusion of the soluble polysulfide species toward the sodium side. As an important finding, the Na+ conduction within the solid electrolyte phase and across the two liquid/solid interfaces results in only small overpotentials. Also, the thermodynamic properties of RT-Na/S cells operating at room temperature are discussed and compared with the currently much more studied RT-Li/S cells.
S, Metelmann H, Raiß C, Dürr AK, Janek J, Adelhelm P, Thermodynamics and cell chemistry of room temperature sodium/sulfur
cells with liquid and liquid/solid electrolyte, Journal of Power
Sources 243, 2013
Busche MR, Drossel T, Leichtweiss T, Weber DA, Falk M, Schneider M, Reich ML, Sommer H, Adelhelm P, Janek J Dynamic formation of a solid-liquid electrolyte interphase and its consequences for hybrid-battery concepts, Nature Chemistry 8, 2016
Conversion reactions for sodium-ion batteries
Research on sodium-ion batteries has recently been rediscovered and is currently mainly focused on finding suitable electrode materials that enable cell reactions of high energy densities combined with low cost. Naturally, an assessment of potential electrode materials requires a rational comparison with the analogue reaction in lithium-ion batteries. In this paper, we systematically discuss the broad range of different conversion reactions based on their basic thermodynamic properties and compare them with their lithium analogues. Capacities, voltages, energy densities and volume expansions are summarized to sketch out the scope for future studies in this research field. We show that for a given conversion electrode material, replacing lithium by sodium leads to a constant shift in cell potential DE°(Li-Na) depending on the material class. For chlorides DE°(Li-Na) equals nearly zero. Next to the thermodynamic assessment, results on several conversion reactions between copper compounds (CuS, CuO, CuCl, CuCl2) and sodium are being discussed.
F, Jache B, Bhide A, Adelhelm P, Conversion
reactions for sodium-ion batteries, Phys. Chem. Chem. Phys., 15, 2013
Hydrogen is expected to play an important role as an energy carrier in a future, more sustainable society. However, its compact, efficient, and safe storage is an unresolved issue. One of the main options is solid-state storage in hydrides. Unfortunately, no binary metal hydride satisfies all requirements regarding storage density and hydrogen release and uptake. In this Review we discuss the large impact of nanosizing and –confinement on the hydrogen sorption properties of metal hydrides. We illustrate possible preparation strategies, provide insight into the reasons for changes in kinetics, reversibility and thermodynamics, and highlight important progress in this field.
Jongh PE, Adelhelm P.; Nanosizing and
Nanoconfinement: New Strategies Towards Meeting Hydrogen Storage Goals. Chemsuschem
3, 2011 (Review)
Carbon materials and nanostructures
In this paper, we report on Li storage in hierarchically porous carbon monoliths with a relatively higher graphite-like ordered carbon structure. Macroscopic carbon monoliths with both mesopores and macropores were successfully prepared by using meso-/macroporous silica as a template and using mesophase pitch as a precursor. Owing to the high porosity (providing ionic transport channels) and high electronic conductivity, this porous carbon monolith with a mixed conducting 3D network shows a superior high-rate performance if used as anode material in electrochemical lithium cells. A challenge for future research as to its applicability in batteries is the lowering of the irreversible capacity.
Hu YS, Adelhelm P, Smarsly BM, Hore S, Antonietti M, Maier J., Synthesis of hierarchically porous carbon monoliths with highly ordered microstructure and their application in rechargeable lithium batteries with high-rate capability, Adv. Funct. Mater. 17, 2007
Adelhelm P, Hu YS, Chuenchom L, Antonietti M, Smarsly BM, Maier J.; Generation of hierarchical meso- and macroporous carbon from mesophase pitch by spinodal decomposition using polymer templates, Adv. Mater. 19, 2007
Jache A, Neumann C, Becker J, Smarsly BM, Adelhelm P. Towards commercial products by nanocasting: characterization and lithium insertion properties of carbons with a macroporous, interconnected pore structure, J. Mater. Chem. 22, 2012
Adelhelm P, Cabrera K, Smarsly BM. On the use of mesophase pitch for the preparation of hierarchical porous carbon monoliths by nanocasting, Sci. Technol. Adv. Mater, 13, 2011
Raiß C, Peppler K, Janek J, Adelhelm P, Pitfalls in the chararcterization of sulfur/carbon nanocomposite materials for lithium-sulfur batteries, Carbon, 79, 2014