A5023226022- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Anodic Oxide Films and Nanostructures
- Perovskite Materials and Applications
- Nanoporous metals and alloys
- ZnO doping and properties
- Copper-based nanomaterials and applications
- Conducting polymers and applications
- Block Copolymer Self-Assembly
- Semiconductor materials and devices
- Advancements in Battery Materials
- Supercapacitor Materials and Fabrication
- Laser-Plasma Interactions and Diagnostics
- Semiconductor materials and interfaces
- Dendrimers and Hyperbranched Polymers
- Electronic and Structural Properties of Oxides
- Photonic Crystals and Applications
- TiO2 Photocatalysis and Solar Cells
- Advanced Polymer Synthesis and Characterization
- Magnetic properties of thin films
- Advanced Optical Sensing Technologies
- Laser-induced spectroscopy and plasma
- Nanowire Synthesis and Applications
- Electrochemical sensors and biosensors
- Gas Sensing Nanomaterials and Sensors
Friedrich-Alexander-Universität Erlangen-Nürnberg
2018-2024
Nanyang Technological University
2014-2015
Consejo Superior de Investigaciones Científicas
2008-2015
Instituto de Ciencia de Materiales de Madrid
2010-2015
International Council on Mining and Metals
2010
Various solution-based synthesis methods for common metal oxide nanostructures and associated reaction mechanisms are reviewed.
Graphene quantum dots prove useful in lithium-ion batteries. This work introduces graphene for the first time as surface coating material battery electrodes, exemplified by copper oxide nanowires. The high-rate capability, initial columbic efficiency, and cycle life are improved coating.
Cuprous oxide Cu2O is a promising p-type semiconductor for photoelectrochemical (PEC) solar hydrogen generation because it has suitable bandgap (Eg = 2.0-2.2 eV) and band alignment adapted to water reduction. In addition, metallic Cu earth-abundant thus making low-cost material. However, the reduction potential of into (0.47 V versus RHE) lower than that which induces severe instability under irradiation in PEC cell. Therefore, our recent efforts focused on growth protective overlayer top...
The synthesis of templates with modulated pore channels by combined mild and hard anodization processes is described. pulses, implemented during anodization, are controlled not only in time length amplitude, but also shape: square exponential signals have been applied. Electrodeposition Co subsequently performed to obtain uniform diameter nanowire arrays. Square nanowires imaged scanning electron microscopy hcp hexagonal polycrystalline structure confirmed all nanowires. Magnetic behavior...
The combination of oxide and heavier chalcogenide layers in thin film photovoltaics suffers limitations associated with oxygen incorporation sulfur deficiency the layer or a chemical incompatibility which results dewetting issues defect states at interface. Here, we establish atomic deposition (ALD) as tool to overcome these limitations. ALD allows one obtain highly pure Sb2S3 light absorber layers, exploit this technique generate an additional interfacial consisting 1.5 nm ZnS. This...
Cylindrical Fe28Co67Cu5 nanowires modulated in diameter between 22 and 35 nm are synthesized by electroplating into the nanopores of alumina membranes. High-sensitivity MFM imaging (with a detection noise 1 μN m(-1)) reveals presence single-domain structures remanence with strong contrast at ends nanowires, as well transition regions where is modulated. Micromagnetic simulations suggest that curling magnetization takes place these sites, extending over 10-20 giving rise to stray fields...
Antimony chalcogenides represent a family of materials low toxicity and relative abundance, with high potential for future sustainable solar energy conversion technology. However, cells based on antimony present open-circuit voltage losses that limit their efficiencies. These are attributed to several recombination mechanisms, interfacial being considered as one the dominant processes. In this work, we exploit atomic layer deposition (ALD) grow series ultrathin ZnS layers at TiO2/Sb2S3...
Lead sulfide is deposited from the salts in ‘solution ALD’ mode and converted directly to hybrid perovskite CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub>.
Self-ordering degree of anodic alumina nanopores is related to the volume expansion aluminum oxide. However, little known about how ionic species derived from electrolyte affect parameters inducing self-ordering nanopores. The influence sulfur incorporation into nanoporous oxide (AAO) films on and has been investigated under potentiostatic conditions (14–25 V) in different sulfuric acid electrolytes (3–20 wt %), average current densities each anodization being range 0.1–10 mA cm–2....
Many modern types of solar cells that rely exclusively on earth-abundant non-toxic materials include interfaces between a heavier metal chalcogenide and another type semiconductor. Often, the chemical (adhesion) physical (charge transfer) characteristics those are defining factors for final device performance. Here, we describe ZnS adhesion layer is not sufficient to prevent dewetting Sb2S3 upon annealing thin it an oxidic surface if substrate planar features highly curved surfaces. An...
We establish solution atomic layer deposition (sALD) for the controlled growth of pure Sb2Se3 thin films under mild conditions, namely, room temperature and atmospheric pressure. Upscaling this process yields with high homogeneity over large-area (4″) substrates. Annealing initially amorphous material leads to highly crystalline smooth films. Removing constraints thermal stability sufficient volatility in sALD compared traditional gas-phase ALD opens up a broad choice precursors allows us...
We prepare arrays of cylindrical pores featuring large periods (460 nm and 600 nm) by anodization aluminum. A self-ordered monolayer nanospheres drives the subsequent pore ordering yields a quality order significantly improved with respect to traditional two-step procedure.
Abstract Currently, Sb 2 Se 3 thin films receive considerable research interest as a solar cell absorber material. When completed into device stack, the major bottleneck for further improvement is open‐circuit voltage, which focus of work presented here. Polycrystalline thin‐film absorbers and cells are prepared in substrate configuration dominant recombination path studied using photoluminescence spectroscopy temperature‐dependent current–voltage characteristics. It found that...
TiO<sub>2</sub> nanotubes generated by anodization of metallic titanium sputter-coated on indium tin oxide (ITO) substrates are used as a conductive scaffold for all-solid-state Sb<sub>2</sub>S<sub>3</sub>-sensitized extremely thin absorber (ETA) solar cells.
The growth of nanostructured ZnO thin films on nanoporous anodic alumina substrates (NAAF) by dc reactive magnetron sputtering using a pure Zn metal target is reported.ZnO nanostructures reproduce the pore arrays NAAF used as templates mimicking their hexagonal long range order.Stoichiometric samples were grown with wurtzite type structure, highly textured and oriented in (002) direction.The study size effect final morphology optical properties presented for different thicknesses.The was...
Abstract The preparation of a highly ordered nanostructured transparent electrode based on combination nanosphere lithography and anodization is presented. size perfectly pore domains improved by an order magnitude with respect to the state art. concomitantly reduced density defect pores increases fraction that are in good electrical contact underlying conductive substrate. This improvement structural quality translates directly linearly into performance energy conversion devices built from...
The multi-analytical study of polyaniline samples obtained by in situ microsynthesis was performed.
In this study we report the application of synchrotron X-ray fluorescence, photoluminescence and Raman scattering techniques to analysis incorporation impurities in unintentionally doped ZnO nanowires.Highly ordered one-dimensional arrays were fabricated by an oxidation process Zn metal electrodeposited nanoporous anodic alumina template.X-ray fluorescence data show contribution residual elements into nanowires growth.A rough analytical quantification main light heavy chemical contents...
Unraveling the two-dimensional (2D) structural ordering of colloidal particles assembled at a flat surface is essential for understanding and optimizing their physical properties. So far, grazing-incidence small-angle X-ray scattering (GISAXS) has been widely used to determine crystallographic information on 2D self-assembled structures nanosize objects. However, solving structure lattices consisting micrometer (μm)-sized objects still remains challenge using methods. Here, model SCALMS...