Beatriz Roldan Cuenya
Beatriz Roldan Cuenya
Gerard Meijer
Martin Wolf
Karsten Reuter

Science News

Twisting Under the Stroboscope – Controlling Crystal Lattices of Hybrid Solar Cell Materials with Terahertz Light
To overcome global energy challenges and fight the looming environmental crisis, researchers around the world investigate new materials for converting sunlight into electricity. Some of the most promising candidates for high-efficiency low-cost solar cell applications are based on lead halide perovskite (LHP) semiconductors. Despite record-breaking solar cell prototypes, the microscopic origin of the surprisingly excellent optoelectronic performance of this material class is still not completely understood. Now, an international team of physicists and chemists from Fritz Haber Institute of the Max Planck Society, École Polytechnique in Paris, Columbia University in New York, and the Free University in Berlin demonstrated laser-driven control of fundamental motions of the LHP atomic lattice. By applying a sudden electric field spike faster than a trillionth of a second (picosecond) in the form of a single light cycle of far-infrared Terahertz radiation, the investigators unveiled the ultrafast lattice response, which might contribute to a dynamic protection mechanism for electric charges. This precise control over the atomic twist motions will allow to create novel non-equilibrium material properties, potentially providing hints for designing the solar cell material of the future.

Ångstrom-Depth Resolution with Chemical Specificity at the Liquid-Vapor Interface
Surfactants play an important role in every day life, for instance as major components in soaps.  Since they feature hydrophilic and hydrophobic parts in their structure, they accumulate at water interfaces with air and can there influence the rate of evaporation of the solution or the efficiency with which gas molecules are taken up by the solution, a process that is for instance important for the incorporation of carbon dioxide into the oceans. How surfactants arrange themselves at the interface of water with air is an intriguing question that has fascinated scientist for centuries, going back to Benjamin Franklin who noted the calming effect of cooking oil on the surface of water, and Agnes Pockels who did some of the first systematic experiments on the subject in the late 19th century. The question of the arrangement of surfactant molecules at the water-air interface is not easy to answer since a close look at the very skin of liquid water requires methods that hone in on the outer layers of water, where surfactant molecules are located in a layer with a thickness of only a few billionths of a meter.

Exciton fission – one photon in, two electrons out
Photovoltaics, the conversion of light to electricity, is a key technology for sustainable energy. Since the days of Max Planck and Albert Einstein, we know that light as well as electricity are quantized, meaning they come in tiny packets called photons and electrons. In a solar cell, the energy of a single photon is transferred to a single electron of the material, but no more than one. Only a few molecular materials like pentacene are an exception, where one photon is converted to two electrons instead. This excitation doubling, which is called exciton fission, could be extremely useful for high-efficiency photovoltaics, specifically to upgrade the dominant technology based on silicon. A team of researchers at the Fritz Haber Institute of the Max Planck Society, the Technical University of Berlin, and the Julius-Maximilians-Universität of Würzburg have now deciphered the first step of this process by recording an ultrafast movie of the photon-to-electricity conversion process, resolving a decades-old debate about the mechanism of the process.

Institute News

Successful participation at the 21st IKK BB Berliner Firmenlauf 2023
On a sunny day in May, the Fritz Haber Institute of the Max Planck Society gathered with full energy and enthusiasm at the starting point in Tiergarten for the 21st IKK BB Berliner Firmenlauf 2023. Over 20 dedicated colleagues took part in the race, showcasing not only their athletic performance but also the unity of "Team Fritz".

Helmut Schwarz receives the Gerhard Ertl Lecture Award 2023
An honor for his achievements in the field of chemistry

Alexander von Humboldt Foundation Grant for Dr. Jie Wei
In April, Dr. Jie Wei started his research work in the Helmholtz Young Investigator Group Nanoscale Operando CO2 Photo-Electrocatalysis at Helmholtz-Zentrum Berlin (HZB) and Fritz Haber Institute (FHI) of the Max Planck Society. Wei received one of the highly competitive Humboldt postdoctoral research fellowships and will pursue his two-year project under the guidance of the academic hosts Dr. Christopher Kley and Prof. Dr. Beatriz Roldán Cuenya.

BASF Distinguished Lecture
On April 18th Prof. Dr. Beatriz Roldán Cuenya, Director of the Department for Interface Science at the Fritz Haber Institute, had the honor to receive the Physical Chemistry Lectureship at the University of California, Berkeley.

Current Information

Open Positions

Further job positions can be found also here.

Lighthouse Project CatLab on an international stage
The CatLab project now presented itself very successfully at the international conference on "Challenges on Renewable Energy Storage" in Liblice near Prague. In addition to the FHI, the Helmholtz Centre Berlin and the Max Planck Institute for Chemical Energy Conversion are also involved in the joint catalysis research for better use of green hydrogen.

Upcoming Seminars

Machine Learning Models of Many-body Atomic and Electronic Interactions

May 30, 2023 02:15 PM (Local Time Germany)
IRIS Adlershof, Zum Großen Windkanal 2, 12489 Berlin

Vibrational Circular Dichroism of Molecular Crystals: The Interplay of Symmetry and Chirality

MP Department Seminar
Jun 2, 2023 09:30 AM c.t. - 10:30 AM (Local Time Germany)
Haber Villa, Room: Seminar Room

TH-ISC Seminar: Professor Susannah L. Scott

TH and ISC Seminar
Jun 8, 2023 11:00 AM (Local Time Germany)
Building M, Richard-Willstätter-Haus, Faradayweg 10, 14195 Berlin, Room: Seminar Room

Rovibronic Transitions in Molecules: Toward an Exact Approach

MP Department Seminar
Jun 9, 2023 09:30 AM c.t. - 10:30 AM (Local Time Germany)
Haber Villa, Room: Seminar Room

THz Young Scientists Meeting 2023
The application process for the 13th THz Young Scientists Meeting is open. The event will take place from 14th - 15th September in Berlin.
Go to Editor View