| 31. |
- Berglund, Lars, 1979-, et al.
(författare)
-
Bioinspired Wood Nanotechnology for Functional Materials
- 2018
-
Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 30:19
-
Tidskriftsartikel (refereegranskat)abstract
- It is a challenging task to realize the vision of hierarchically structured nanomaterials for large-scale applications. Herein, the biomaterial wood as a large-scale biotemplate for functionalization at multiple scales is discussed, to provide an increased property range to this renewable and CO2-storing bioresource, which is available at low cost and in large quantities. The Progress Report reviews the emerging field of functional wood materials in view of the specific features of the structural template and novel nanotechnological approaches for the development of wood-polymer composites and wood-mineral hybrids for advanced property profiles and new functions.
|
|
| 32. |
- Bing, Zhao, 1990, et al.
(författare)
-
Unconventional Charge–Spin Conversion in Weyl-Semimetal WTe2
- 2020
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 32:38
-
Tidskriftsartikel (refereegranskat)abstract
- An outstanding feature of topological quantum materials is their novel spin topology in the electronic band structures with an expected large charge-to-spin conversion efficiency. Here, a charge-current-induced spin polarization in the type-II Weyl semimetal candidate WTe2 and efficient spin injection and detection in a graphene channel up to room temperature are reported. Contrary to the conventional spin Hall and Rashba–Edelstein effects, the measurements indicate an unconventional charge-to-spin conversion in WTe2, which is primarily forbidden by the crystal symmetry of the system. Such a large spin polarization can be possible in WTe2 due to a reduced crystal symmetry combined with its large spin Berry curvature, spin–orbit interaction with a novel spin-texture of the Fermi states. A robust and practical method is demonstrated for electrical creation and detection of such a spin polarization using both charge-to-spin conversion and its inverse phenomenon and utilized it for efficient spin injection and detection in the graphene channel up to room temperature. These findings open opportunities for utilizing topological Weyl materials as nonmagnetic spin sources in all-electrical van der Waals spintronic circuits and for low-power and high-performance nonvolatile spintronic technologies.
|
|
| 33. |
- Bjurstrom, Anton, et al.
(författare)
-
A Review of Polyolefin-Insulation Materials in High Voltage Transmission; From Electronic Structures to Final Products
- 2024
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095.
-
Forskningsöversikt (refereegranskat)abstract
- This review focuses on the use of polyolefins in high-voltage direct-current (HVDC) cables and capacitors. A short description of the latest evolution and current use of HVDC cables and capacitors is first provided, followed by the basics of electric insulation and capacitor functions. Methods to determine dielectric properties are described, including charge transport, space charges, resistivity, dielectric loss, and breakdown strength. The semicrystalline structure of polyethylene and isotactic polypropylene is described, and the way it relates to the dielectric properties is discussed. A significant part of the review is devoted to describing the state of art of the modeling and prediction of electric or dielectric properties of polyolefins with consideration of both atomistic and continuum approaches. Furthermore, the effects of the purity of the materials and the presence of nanoparticles are presented, and the review ends with the sustainability aspects of these materials. In summary, the effective use of modeling in combination with experimental work is described as an important route toward understanding and designing the next generations of materials for electrical insulation in high-voltage transmission.
|
|
| 34. |
- Bobbert, Peter A., et al.
(författare)
-
Operational Stability of Organic Field-Effect Transistors
- 2012
-
Ingår i: Advanced Materials. - : Wiley-VCH Verlag. - 0935-9648 .- 1521-4095. ; 24:9, s. 1146-1158
-
Tidskriftsartikel (refereegranskat)abstract
- Organic field-effect transistors (OFETs) are considered in technological applications for which low cost or mechanical flexibility are crucial factors. The environmental stability of the organic semiconductors used in OFETs has improved to a level that is now sufficient for commercialization. However, serious problems remain with the stability of OFETs under operation. The causes for this have remained elusive for many years. Surface potentiometry together with theoretical modeling provide new insights into the mechanisms limiting the operational stability. These indicate that redox reactions involving water are involved in an exchange of mobile charges in the semiconductor with protons in the gate dielectric. This mechanism elucidates the established key role of water and leads in a natural way to a universal stress function, describing the stretched exponential-like time dependence ubiquitously observed. Further study is needed to determine the generality of the mechanism and the role of other mechanisms.
|
|
| 35. |
- Bobek, Thomas, et al.
(författare)
-
Self-organized hexagonal patterns of independent magnetic nanodots
- 2007
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 19:24, s. 4375-
-
Tidskriftsartikel (refereegranskat)abstract
- A method for producing self-organised arrays of nanometric metallic dots is reported. It consists on developing first the nanodot pattern by ion erosion on a semiconductor cover film and transferring it to a previously buried metallic layer. This procedure has been applied to Co, and the ferromagnetic behaviour of the dots at room temperature is demonstrated.
|
|
| 36. |
- Bohme, O, et al.
(författare)
-
Nanoparticles as the active element of high-temperature metal-insulator-silicon carbide gas sensors
- 2001
-
Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 13:8, s. 597-
-
Tidskriftsartikel (refereegranskat)abstract
- The sensor performance of MISiC (metal-insulator-silicon carbide) diode devices depends on their temperature pretreatment: an activation step at 600 degreesC leads to fast-responding devices with extraordinarily high signals but the devices fail when operated above 700 degreesC. The authors focus on the key role of nanoparticles in high-temperature gas sensor applications of these MISiC devices, presenting a model in which the interface dipole moment of nanoparticles is seen as the driving force and explaining the difference in response of capacitor-configuration and Schottky-diode-configuration devices.
|
|
| 37. |
- Bolin, Maria, et al.
(författare)
-
Active Control of Epithelial Cell-Density Gradients Grown Along the Channel of an Organic Electrochemical Transistor
- 2009
-
Ingår i: ADVANCED MATERIALS. - : Wiley. - 0935-9648 .- 1521-4095. ; 21:43, s. 4379-
-
Tidskriftsartikel (refereegranskat)abstract
- Complex patterning of the extracellular matrix, cells, and tissues under in situ electronic control is the aim of the technique presented here. The distribution of epithelial cells along the channel of an organic electrochemical transistor is shown to be actively controlled by the gate and drain voltages, as electrochemical gradients are formed along the transistor channel when the device is biased.
|
|
| 38. |
- Boström, Hanna L. B., et al.
(författare)
-
How Reproducible is the Synthesis of Zr-Porphyrin Metal-Organic Frameworks? An Interlaboratory Study
- 2024
-
Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 36:15
-
Tidskriftsartikel (refereegranskat)abstract
- Metal-organic frameworks (MOFs) are a rapidly growing class of materials that offer great promise in various applications. However, the synthesis remains challenging: for example, a range of crystal structures can often be accessed from the same building blocks, which complicates the phase selectivity. Likewise, the high sensitivity to slight changes in synthesis conditions may cause reproducibility issues. This is crucial, as it hampers the research and commercialization of affected MOFs. Here, it presents the first-ever interlaboratory study of the synthetic reproducibility of two Zr-porphyrin MOFs, PCN-222 and PCN-224, to investigate the scope of this problem. For PCN-222, only one sample out of ten was phase pure and of the correct symmetry, while for PCN-224, three are phase pure, although none of these show the spatial linker order characteristic of PCN-224. Instead, these samples resemble dPCN-224 (disordered PCN-224), which has recently been reported. The variability in thermal behavior, defect content, and surface area of the synthesised samples are also studied. The results have important ramifications for field of metal-organic frameworks and their crystallization, by highlighting the synthetic challenges associated with a multi-variable synthesis space and flat energy landscapes characteristic of MOFs. It performed an interlaboratory study of the synthesis of the metal-organic frameworks (MOFs) PCN-222 and PCN-224. Ten participants independently synthesized the two MOFs and the products are analyzed, primarily by X-ray diffraction. The success rates are low (one-three samples corresponding to a pure sample of the correct phase), thus highlighting the problems with irreproducibility in MOF synthesis. image
|
|
| 39. |
- Boxberg, Fredrik, et al.
(författare)
-
Elastic and Piezoelectric Properties of Zincblende and Wurtzite Crystalline Nanowire Heterostructures.
- 2012
-
Ingår i: Advanced Materials. - : Wiley. - 1521-4095 .- 0935-9648. ; 24:34, s. 4692-4706
-
Tidskriftsartikel (refereegranskat)abstract
- The elastic and piezoelectric properties of zincblende and wurtzite crystalline InAs/InP nanowire heterostructures have been studied using electro-elastically coupled continuum elasticity theory. A comprehensive comparison of strains, piezoelectric potentials and piezoelectric fields in the two crystal types of nanowire heterostructures is presented. For each crystal type, three different forms of heterostructures-core-shell, axial superlattice, and quantum dot nanowire heterostructures-are considered. In the studied nanowire heterostructures, the principal strains are found to be insensitive to the change in the crystal structure. However, the shear strains in the zincblende and wurtzite nanowire heterostructures can be very different. All the studied nanowire heterostructures are found to exhibit a piezoelectric field along the nanowire axis. The piezoelectric field is in general much stronger in a wurtzite nanowire heterostructure than in its corresponding zincblende heterostructure. Our results are expected to be particularly important for analyzing and understanding the properties of epitaxially grown nanowire heterostructures and for applications in nanowire electronics, optoelectronics, and biochemical sensing.
|
|
| 40. |
- Braun, Slawomir, et al.
(författare)
-
Energy-Level Alignment at Organic/Metal and Organic/Organic Interfaces
- 2009
-
Ingår i: ADVANCED MATERIALS. - : Wiley. - 0935-9648 .- 1521-4095. ; 21:14-15, s. 1450-1472
-
Forskningsöversikt (refereegranskat)abstract
- In this Review, we summarize recent work on modeling of organic/metal and organic/organic interfaces. Some of the models discussed have a semiempirical approach, that is, experimentally derived values are used in combination with theory, and others rely completely of calculations. The models are categorized according to the types of interfaces they apply to, and the strength of the interaction at the interface has been used as the main factor. We explain the basics of the models, their use, and give examples on how the models correlate with experimental results. We stress that given the complexity of organic/metal and organic/organic interface formation, it is crucial to know the exact way in which the interface was formed before choosing the model that is applicable, as none of the models presented covers the whole range of interface interaction strengths (weak physisorption to strong chemisorption).
|
|
