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Arrays of vertically aligned Si-nanopillars, with average diameters of 100 nm and 5 μm length, have been prepared by wet chemical etching of crystalline silicon in a special manner. Samples with smooth- and porous-walled nanopillars have been studied. In the case of the latter, Si-nanocrystals, passivated with SiO(x), decorating the surface of the nanopillars are identified by the means of TEM and FTIR. When excited by UV-blue light, the porous-walled Si-nanopillars are found to have a strong broad visible emission band around 1.8 eV with a nearly perfect Gaussian shape, μs luminescence lifetimes, minor emission polarization and a non-monotonic temperature dependence of luminescence. The Si-nanocrystal surface is found to be responsible for the luminescence. The red-shift of the emission maximum and the luminescence quenching induced by oxidation in UV-ozone confirm this assumption. A model of luminescence involving UV photon absorption by Si-nanocrystals with subsequent exciton radiative recombination on defect sites in SiO(x) covering Si-nanocrystals has been proposed. Possible applications of the nanopillar arrays are discussed.
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http://dx.doi.org/10.1088/0957-4484/23/47/475709 | DOI Listing |
PLoS Comput Biol
September 2025
Mathematical and Statistical Methods (Biometris), Wageningen University, Wageningen, The Netherlands.
Many plant cell functions, including cell morphogenesis and anisotropic growth, rely on the self-organisation of cortical microtubules into aligned arrays with the correct orientation. An important ongoing debate is how cell geometry, wall mechanical stresses, and other internal and external cues are integrated to determine the orientation of the cortical array. Here, we demonstrate that microtubule-based nucleation can markedly shift the balance between these often competing directional cues.
View Article and Find Full Text PDFAdv Sci (Weinh)
September 2025
Thin Film Materials Research Center, Korea Research Institute of Chemical Technology, Daejeon, 34114, Republic of Korea.
Molybdenum disulfide (MoS) has recently emerged as a promising material for the development of triboelectric nanogenerators (TENGs) owing to its inherently negative triboelectric properties when paired with polymeric layers, along with its notable transparency and mechanical flexibility. However, MoS-based TENGs operating in the contact-separation mode encounter critical limitations, including mechanical wear and limited triboelectric performance, particularly within the constraints of conventional 2D geometries. This paper reports the novel one-step laser-assisted synthesis of hemispherical MoS through the controlled nucleation and growth of MoS precursor seeds.
View Article and Find Full Text PDFAdv Sci (Weinh)
September 2025
Guangxi Key Laboratory of Clean Pulp & Papermaking and Pollution Control, School of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China.
Carbonized wood has great potential as a self-supported electrode for energy storage/conversion applications. However, developing efficient and economical bifunctional electrodes by customizing the surface structure remains a challenge. This study proposes a novel multifunctional electrode design strategy, using N/P co-doped carbonized wood (NPCW) as carriers and in situ grows copper nanoparticles (Cu NPs) as nucleation centers to induce vertical growth of CuCo-layered double hydroxid (LDH) nanosheets along the substrate.
View Article and Find Full Text PDFACS Sens
September 2025
The State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Tactile sensing arrays play a crucial role in human-machine interaction, robotics, and artificial intelligence by enabling the perception of physical stimuli on robotic surfaces or human skin. However, skin-attachable sensor arrays still suffer from strain interference and signal crosstalk under stretching or bending, particularly on curved or deformable surfaces. Here, we present a stretchable tactile array that is both strain-insensitive and crosstalk-suppressed, achieved via a hierarchically segmented design that mitigates lateral and vertical deformations synergistically.
View Article and Find Full Text PDFSci Adv
September 2025
Australian Research Council Centre of Excellence for Transformative Meta-Optical Systems, Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2600, Australia.
Surface-emitting lasers featuring optical bound states in the continuum (BICs) have recently emerged as a promising alternative to vertical cavity surface-emitting lasers. However, structural damage caused by top-down fabrication processes remains as a major obstacle that limits device performance. Here, we overcome this bottleneck by demonstrating surface-emitting quasi-BIC lasers fabricated with a bottom-up, etching-free process.
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