A5045030207- Advanced Photocatalysis Techniques
- Gas Sensing Nanomaterials and Sensors
- Particle Dynamics in Fluid Flows
- Copper-based nanomaterials and applications
- nanoparticles nucleation surface interactions
- Electronic and Structural Properties of Oxides
- TiO2 Photocatalysis and Solar Cells
- Inorganic Chemistry and Materials
- Nuclear Materials and Properties
- Catalytic Processes in Materials Science
- Ferroelectric and Piezoelectric Materials
- Coagulation and Flocculation Studies
- Enzyme Structure and Function
- Electrocatalysts for Energy Conversion
- Advancements in Solid Oxide Fuel Cells
- Fuel Cells and Related Materials
- Nuclear materials and radiation effects
- Ga2O3 and related materials
- Advanced ceramic materials synthesis
- Fusion materials and technologies
- Hydrogen Storage and Materials
- Groundwater flow and contamination studies
- Minerals Flotation and Separation Techniques
- Microwave Dielectric Ceramics Synthesis
- Fluid Dynamics and Turbulent Flows
Leibniz Institute for Plasma Science and Technology
2023
University of Freiburg
2016-2019
Technische Universität Berlin
2014-2019
University of Education Freiburg
2018
Max Planck Institute for Dynamics and Self-Organization
2011-2014
Max Planck Society
2014
University of Göttingen
2011-2014
Hydrogen barrier coatings are protective layers consisting of materials with a low intrinsic hydrogen diffusivity and solubility, showing the potential to delay, reduce or hinder permeation. expected enable steels, which susceptible embrittlement, specifically cost-effective alloy-steels light-weight high-strength for applications in economy. Predominantly, ceramic coating have been investigated this purpose, including oxides, nitrides carbides. In review, state art respect permeation is...
Facile sol–gel synthesis of Mo:BiVO<sub>4</sub> thin films with optimized morphology results in reduced surface recombination and enhanced hole transfer efficiency.
Anion substitution is an emerging strategy to enhance the photoelectrochemical performance of metal oxide photoelectrodes. In present work, we investigate effect fluorine incorporation on water oxidation BiVO4 and Mo:BiVO4 thin film photoanodes. The photoanodes were prepared by a straightforward organometallic solution route involving dip coating subsequent calcination in air. Fluorine modification was realized applying soft low-cost solid–vapor reaction fluorine-containing polymers inert...
Photocorrosion imposes a fundamental limit to the longevity of devices that harvest energy from photons. As one best performing electrode materials for photoelectrochemical water oxidation reaction, BiVO4 undergoes photocorrosion with various postulated mechanisms under debate. We present time-resolved dissolution measurements advance mechanistic understanding, enabled by recent development in illuminated scanning flow cell coupled inductively plasma mass spectrometry. The contact...
We explore the evolution of aggregate size distribution in systems where aggregates grow by diffusive accretion mass. Supersaturation is controlled such a way that overall volume grows linearly time. Classical Ostwald ripening, which recovered limit vanishing growth, constitutes an unstable solution dynamics. In presence growth evaporation always drives dynamics into new, qualitatively different regime ripening ceases, and proceeds at constant number density aggregates. provide comprehensive...
Abstract A new phase in the system Sc‐Ta‐O‐N was synthesized by reaction of an amorphous oxide precursor with a gaseous NH 3 /O 2 mixture at 800 °C. Crystal structure determination performed using X‐ray powder data. ScTa O 5 N crystallizes tetragonal space group P 4 / mnm (rutile‐type structure) and exhibits brilliant yellow color (optical bandgap: 2.67 eV), making it promising material for photocatalytical water splitting. Further investigation methods (SEM, TEM, ‐physisorption) were...
Abstract The importance of the synthesis conditions on structural and photocatalytic properties tantalum oxide nitride was investigated by comparing two variants phase-pure β -TaON obtained from application different routes, leading to one unstrained heavily anisotropically microstrained as shown XRD-based Rietveld refinement. HRTEM images reveal origin strain be lattice defects such stacking faults. strained found clearly less active semiconductor in photochemical photoelectrochemical water...
Abstract BiVO 4 is one of the most investigated and promising metal oxide based photoanode materials for photoelectrochemical (PEC) water oxidation. Although it has several advantages (suitable band gap around 2.4 eV, suitable valence-band position oxidation, low toxicity, high abundance), suffers from slow charge-carrier transport properties, surface recombination, limited water-oxidation activity. In present work, we review synthesis doping strategies that developed in last years to...
When a binary fluid demixes under slow temperature ramp, nucleation, coarsening and sedimentation of droplets lead to an oscillatory evolution the phase-separating system. The advection sedimenting is found be chaotic. flow driven by density differences between two phases. Here, we show how image processing can combined with particle tracking resolve droplet size velocity simultaneously. Droplets are used as tracer particles, determined. Taking these effects into account, radii in range 4−40...
Hydrogen barrier coatings are important for future hydrogen economy to enable materials applications in tanks. In the present study, consisting of amorphous Al 2 O 3 (≈100 nm) synthesized by plasma ion‐assisted deposition on top crystalline metallic exposed 300 bar pressure at 673 K 6 days. This is done mimic and accelerate conditions storage containers hydrides. They remain intact after such harsh conditions, although changes do occur. Blister‐like features observed a buckled oxide layer...
The demixing of a binary fluid mixture, under gravity, is two stage process. Initially droplets, or in general aggregates, grow diffusively by collecting supersaturation from the bulk phase. Subsequently, when droplets have grown to size, where their Peclet number order unity, buoyancy substantially enhances droplet growth. dynamics approaches finite-time singularity are removed system precipitation. growth regimes separated bottleneck minimal Here, we present low-dimensional model...
This paper is a comment to M Wilkinson, EPL 106 (2014) 40001, arXiv:1401.4620 [physics.ao-ph,cond-mat.soft], which draws conclusion from our data that are at variance with observations.
Abstract The title compound is prepared by oxidizing ammonolysis of an amorphous Sc‐Ta‐O precursor derived Pechini‐type sol‐gel processing (800 °, 2 h, NH 3 and O flow rates 10 0.1 l/h, resp., phase purity 90%).
Metallic bipolar plates in fuel cells have the advantages of high electrical conductivity, low permeability to reactants and gases, easy manufacturability. However, resistance corrosion under long term operation conditions limits their practical use cell. Owing importance stability, materials such as austenitic stainless steels, Ni-based alloys coated titanium or steel are currently being used plates, although ferritic steels would be cost effective. A pinhole-free anticorrosion coating can...
Conducting metal@metal oxide structures are promising materials to overcome the limitations of state-of-the-art fuel cell catalysts based on carbon as support material, which suffer from corrosion and metal nanoparticle sintering. One interesting is titanium oxide, shows high stability under operating conditions [1-3]. Also due electronic effects catalytic properties supported platinum nanoparticles can be tuned by supports, leading increased activity or better poisoning tolerance, main...
The Ba 0.5 Sr Co 0.8 Fe 0.2 O 3-δ (BSCF) mixed ionic electronic conductor (MIEC) is considered to be one of the most promising perovskite-based materials for oxygen transport exhibiting high permeability. Such oxygen-permeable perovskite membrane maybe applied increase efficiency combustion or reforming processes new fuels such as green ammonia. An approach elevate permeability BSCF membranes reduction thickness, permeation process mostly controlled by bulk diffusion. Since self-standing...