A5031950017- Diamond and Carbon-based Materials Research
- Force Microscopy Techniques and Applications
- Semiconductor materials and devices
- Metal and Thin Film Mechanics
- Electrochemical Analysis and Applications
- Electronic and Structural Properties of Oxides
- Chemical Reactions and Mechanisms
- Analytical Chemistry and Sensors
- Conducting polymers and applications
- Nanowire Synthesis and Applications
- Structural and Chemical Analysis of Organic and Inorganic Compounds
- Asymmetric Hydrogenation and Catalysis
- Fluorine in Organic Chemistry
- Atomic and Subatomic Physics Research
- Advanced MRI Techniques and Applications
- Chemical Synthesis and Analysis
- Mechanical and Optical Resonators
- Characterization and Applications of Magnetic Nanoparticles
- Advancements in Semiconductor Devices and Circuit Design
- Integrated Circuits and Semiconductor Failure Analysis
- Synthesis and Reactions of Organic Compounds
- Asymmetric Synthesis and Catalysis
- Ion-surface interactions and analysis
- Biochemical and Molecular Research
- Radical Photochemical Reactions
Fraunhofer Institute for Applied Solid State Physics
2017-2025
University of Freiburg
2018
Universität Ulm
2012-2017
National Research Council Canada
1979
University of British Columbia
1971
A microfluidic platform for solid-state quantum sensing, enabling the measurement of various physical quantities lab-on-a-chip applications.
Solvated electrons are highly reductive chemical species whose properties remain largely unknown. Diamond materials proposed as a promising emitter of solvated and visible light excitation would enable solar-driven CO2 or N2 reductions reactions in aqueous medium. But sub-bandgap remains challenging. In this work, the role surface states on diamond for charge separation emission both gaseous environments from deep UV to is elucidated. Four different X-ray UV-vis spectroscopy methods applied...
Understanding diffusion in microstructures plays a crucial role many scientific fields, including neuroscience, medicine, or energy research. While magnetic resonance (MR) methods are the gold standard for measurements, spatial encoding MR imaging has limitations. Here, we introduce nitrogen-vacancy (NV) center–based nuclear (NMR) spectroscopy as powerful tool to probe within microscopic sample volumes. We have developed an experimental scheme that combines pulsed gradient spin echo (PGSE)...
Soft electronic devices play a crucial role in, e.g., neural implants as stimulating electrodes, transducers for biosensors, or selective drug-delivery. Because of their elasticity, they can easily adapt to environment and prevent immunoreactions leading an overall improved long-term performance. In addition, flexible such stretchable displays will be increasingly used in everyday life, so-called wearables. Atomic force microscopy (AFM) is versatile tool characterize these micro-...
We introduce a novel conductive colloidal Atomic Force-Scanning Electrochemical Microscopy (AFM-SECM) probe for single cell force spectroscopy that enables detection of and molecular-level interactions at electromaterial interfaces whilst applying electrical stimulation.
Mechanical forces affect biological systems in their natural environment a widespread manner. stress may either stimulate cells or even induce pathological processes. Cells sensing mechanical usually respond to such stressors with proliferation differentiation. Hence, for vitro studies, the ability impose controlled on combined appropriate analytical tools providing an immediate answer is essential understand fundamental Here, we present novel uniaxial motorized cell stretching device that...
We demonstrate a highly efficient, single-step, cathodic exfoliation process of graphite to produce single- few-layer graphene with yield over 70% from natural flakes. By employing boron-doped diamond electrodes high potentials up -60 V can be applied which was found greatly increase the yield. The produced flakes are partially hydrogenated during electrochemical treatment likely aiding in their exfoliation. resulting have large lateral size 50 μm diameter. Due reversibility hydrogenation by...
The interplay between photo- and electrochemical reactions fundamentally influences charge transfer processes at solid-liquid interfaces. Nevertheless, chemical semiconductor surfaces triggered by light excitation under applied potential remain poorly explored. This work deciphers the synergistic role of on boron-doped diamond electrodes in producing either surface redox or emission solvated electrons water. termination electron affinity, band bending, extraction is identified a...
The direct experimental characterization of diffusion processes at nanoscale remains a challenge that could help elucidate in biology, medicine and technology. In this report, two approaches were employed to visualize ion profiles the orifices nanopores (radius (ra) 86 ± 6 nm) array format: (1) electrochemically assisted formation silica deposits based on surfactant transfer across nanointerfaces between immiscible electrolyte solutions (nanoITIES); (2) combined atomic force - scanning...
For the wafer-scale fabrication of diamond devices, growth substrates by heteroepitaxial chemical vapor deposition is most promising option currently available. However, transfer and also structuring processes from small homoepitaxial to larger samples not straightforward requires adaptation. In this study, we present an approach for functional microstructures including pyramids mesas as well more complex structures with hollow centers. The associated methods were previously demonstrated are...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTKinetics of acid-catalyzed hydration 1,3-butadienes and vinyl halides. Correlation the reactivity alkenes aryl alkenesWilly K. Chwang, P. Knittel, M. Koshy, Thomas T. TidwellCite this: J. Am. Chem. Soc. 1977, 99, 10, 3395–3401Publication Date (Print):May 1, 1977Publication History Published online1 May 2002Published inissue 1 1977https://doi.org/10.1021/ja00452a035Request reuse permissionsArticle Views480Altmetric-Citations28LEARN ABOUT THESE...
Platinum (Pt) has been known as a catalyst material for vapor-liquid-solid (VLS) synthesis since the mid 1960s with potential to grow electronic grade silicon nanowires (SiNWs). In contrast gold-based growth, Pt-catalyzed SiNW rarely studied, most likely due higher temperatures and formation of multiple Pt silicide phases. Here we present growth SiNWs from deposited by focused ion or electron beam, which opens new strategies assembly SiNW-based devices, well nanoparticles thin films. We show...
A microwave plasma reactor for diamond growth that allows highly controllable process conditions is presented. The position of the substrate within can be accurately controlled. Thus, equilibration carried out after changes in parameters. With this approach, sharp layer transitions among doped, undoped, and isotopically controlled films obtained. In addition to sample transfer, temperature maintained through a heater, clean environment realized by load‐lock exchange system. are constantly...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAcid-catalyzed hydration of 1,2-disubstituted alkenesPeter Knittel and Thomas T. TidwellCite this: J. Am. Chem. Soc. 1977, 99, 10, 3408–3414Publication Date (Print):May 1, 1977Publication History Published online1 May 2002Published inissue 1 1977https://pubs.acs.org/doi/10.1021/ja00452a037https://doi.org/10.1021/ja00452a037research-articleACS PublicationsRequest reuse permissionsArticle Views533Altmetric-Citations26LEARN ABOUT THESE METRICSArticle...
Synergistic effect of nanostructuration and boron doping allows sub-bandgap electron acceptor states in diamond materials to be controlled.
The characterization of nanoparticles and the correlation physical properties such as size shape to their (electro)chemical is an emerging field, which may facilitate future optimization tuning devices involving nanoparticles. This requires investigation individual particles rather than obtaining averaged information on large ensembles. Here, we present atomic force – scanning electrochemical microscopy (AFM-SECM) measurements soft conductive PDMS substrates modified with gold nanostars...
Abstract Conductive, boron doped diamond (BDD) is an extraordinary material with many applications in electrochemistry due to its wide potential window, outstanding robustness, low capacitance and resistance fouling. However, photoelectrochemistry, BDD usually requires UV light for excitation, which impedes e. g., usage CO 2 fuel reduction. In this work, a heavily doped, nanostructured electrode enhanced absorption has been developed. It manufactured from by reactive ion etching presents...
Abstract Diamond enables the construction of various (bio)sensors, including those with quantum‐based detection. However, bare diamond interfaces are susceptible to unspecific adhesion proteins and other macromolecules from biological media or complex samples. This impairs selectivity in biosensing, leads low signal‐to‐noise ratio fluorescence‐based applications, introduces need for blocking steps incubation protocols. Here, a stable, protein‐repellent, clickable reactive polymer coating is...
Due to fascinating physical properties powered by remarkable progress in chemical vapor deposition of high-quality epilayers, diamond thin films attract great attention for fabrication nitrogen-vacancy-based solid-state spin systems capable operating ambient conditions. To date, heteroepitaxy via bias-enhanced nucleation is an unavoidable method reliable wafer-scale film manufacturing. In this work, we analyze the coalescence phenomena nitrogen doped, heteroepitaxial with a particular focus...
Heteroepitaxial chemical vapor deposition is the most promising option to fabricate wafer-scale monocrystalline diamonds for quantum applications. Previously, we demonstrated feasibility manufacture functional micrometer-sized pyramids on as-grown heteroepitaxial diamond as well their optical characteristics. Due high background signals and microfabrication challenges, these could not compete with homoepitaxially grown structures. In this study, overcame problems a nominally undoped buffer...