Multi-layered and ultra-lightweight 3D framework structures enabled by combining different film deposition technologies
Conventional soft conductors are characterized by a large change in electrical conductance upon mechanical deformation. In a recent joint work with the Chair for Functional Nanotechnology (Prof. Adelung) we combine thin film deposition technologies in a three-dimensional fashion, resulting in multi-layered and ultra-lightweight foam-like framework structures based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), coated with polytetrafluoroethylene. These all-organic soft conductors show strain-invariant conductance over a large strain range, super elastic deformation and water stability.
Article
Nanoscale Synergetic Effects on Ag–TiO2 Hybrid Substrate for Photoinduced Enhanced Raman Spectroscopy (PIERS) with Ultra-Sensitivity and Reusability
In a recently published paper, we present an ultra-sensitive photoinduced enhanced Raman spectroscopy (PIERS) method to detect analytes at extremely low concentrations (one to three orders of magnitude lower than that of surface-enhanced Raman spectroscopy, SERS) by using a novel substrate named as 4N-in-1. 4N-in-1 substrate can be re-used for diagnostic and forensic applications at least 20 times by simple photocatalytic degradation. More detail can be found in the article link.
Nanoscale gradient copolymer films via single-step deposition from the vapor phase
In a recent publication we report on the deposition of novel nanoscale gradient copolymer films via initiated chemical vapor deposition (iCVD). In these films the chemical composition changes gradually from polymer type A to polymer type B. By enhancing the iCVD process with in-situ mass spectrometry, we were able to produce these materials at film thicknesses below 30 nm. The combination of two material states in one material opens up completely new chemical and physical properties that cannot be achieved with materials currently in use. The results are published in a recent article in the journal Materials Today (click link for further details).
For further information also see the recently published press release "Nanobeschichtungen mit vielen Funktionen" by the Uni Kiel.
Cauliflower-like CeO2-TiO2 thin film photocatalysts
Recently, we demonstrated that cauliflower-like CeO2-TiO2 hybrid thin film structure which can be a promising candidate for photocatalytic and self-cleaning (outdoor/indoor) applications. Cauliflower-like CeO2-TiO2 hybrid photocatalyst exhibited excellent photocatalytic activity to the confined structure of the CeO2-TiO2 interface, which allows dynamic shifting between Ce3+ and Ce4+ oxidation states and improves the separation of photogenerated electron-hole pairs. The article was selected as a back cover in RSC-Nanoscale (click link for further details).
Hierarchical structures by photodegradation
Recently we demonstrated a novel method which utilizes photocatalytic reaction on a highly active titania film to synthesize needle-like gold structures. By irradiating titania surface we are successful to position and pattern hierarchical gold structures without using any costly and time consuming lithographic processes, which open a door to various catalysis, sensor and biomedical applications.The article was selected as cover article. Further information (Link to publication).
Nanogranular Gold Structures
In cooperation with DESY Hamburg and Technical University of Munich researchers from our group applied surface-sensitive X-ray scattering for real time in-situ studies of ultra-thin metallic thin film growth.
For further details see press release and publication.
Alloy nanoparticles with controlled composition
For the deposition of nanoparticles from gas aggregation source (Haberland type), typically homogenous targets are used. Vahl et al. presented a more complex target geometry that allows for deposition of alloy nanoparticles with an in-situ capability of tailoring the nanoparticle composition.The article was selected as cover and feature article. Further information (Link to publication).
Liquids with permanent porosity
Understanding porous liquids
Applying Positron Annihilation Lifetime Spectroscopy, Tönjes Koschine and Klaus Rätzke proved the existence of permanent porosity in liquids in an international collaboration.
For further details see Research paper and Press release (German).
Neue Erkenntnisse über metallische Schmelzen: Was Einstein nicht ahnte
Press release (German).
Copyright:
Left and middle: Elisabeth Gill
Right: Alexander Vahl