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These findings facilitate a better control of tunable nanostructures and optical functionalities. Future research directions are proposed, including morphological control of the secondary phase to enhance its homogeneity, coupling nitrides with magnetic phase for the magneto-optical effect and growing all-ceramic nanocomposites to extend functionalities and anisotropy.Monoelemental two-dimensional (2D) group-VA materials have received increasing interest due to their great potential in optoelectronic applications. Despite numerous efforts have been made for their syntheses, the development of effective and better controllable synthetic approaches for the preparation of monoelemental 2D group-VA materials is still in its infancy. In this work, we report a soft-template approach for the synthesis of multilayered antimonene and bismuthene nanosheets in colloidal solutions. We show that the prepared antimonene and bismuthene nanosheets possess a well-defined rhombohedral crystal structure with impressive stability. We elucidate a formation pathway for the 2D nanosheets with small-angle X-ray diffraction (XRD) analysis. We demonstrate that SbCl3 dissolves in alkyl phosphonic acids to form a lamellar structure initially, which is apt for the formation of the final 2D morphology. The present study introduces a general route to synthesizing monoelemental 2D group-VA materials in colloidal solutions and gives a deeper insight into their growth mechanism.Zinc phosphide (Zn3P2) nanowires constitute prospective building blocks for next generation solar cells due to the combination of suitable optoelectronic properties and an abundance of the constituting elements in the Earth's crust. The generation of periodic superstructures along the nanowire axis could provide an additional mechanism to tune their functional properties. Here we present the vapour-liquid-solid growth of zinc phosphide superlattices driven by periodic heterotwins. This uncommon planar defect involves the exchange of Zn by In at the twinning boundary. We find that the zigzag superlattice formation is driven by reduction of the total surface energy of the liquid droplet. The chemical variation across the heterotwin does not affect the homogeneity of the optical properties, as measured by cathodoluminescence. The basic understanding provided here brings new propsects on the use of II-V semiconductors in nanowire technology.Helix is an important secondary structure in proteins and polypeptides, which, however, has rarely been recognized in amino acids or their simple derivatives. In this work, we firstly unveil the generic existence of supramolecular helical secondary structures in solid-state N-protected amino acids. Throughout searching in Cambridge Structural Database followed by screening, ∼10% N-protected amino acids were evidenced to form H-bonded helical structures, thus covering 15 coded amino acids and diverse types of protecting groups. Helical structures were typically classified as 21 and 31 symmetry, and specific double-strand helical structures were discovered. Computational studies on the calculated electronic circular dichroism spectra show well-defined correlation to experimental results, indicative of the supramolecular secondary structures that possess feature Cotton effects similar to naturally occurring α-helices in proteins. Such feature Cotton effects could be transferred to protecting groups, which is of vital significance to the emerging chiroptical materials. click here This work highlighting the neglected structural analysis would offer a better understanding and deep insight into the structure relationship on the supramolecular chiral materials, crystal engineering and chiroptical materials based on amino acids and their derivatives.γ-Al2O3 nanosheet supported rhodium catalysts with Rh loadings between 0.05 and 2 wt% were prepared by the impregnation method and used for dry reforming of methane (DRM). It was found that Rh species on γ-Al2O3 nanosheets demonstrated excellent stability against sintering at high temperature. After calcining in air at 800 °C followed by reducing with hydrogen at 600 °C, the average particle size of Rh at maximum distribution increases from 1.0 ± 0.3 to 1.8 ± 0.3 nm with an increase in Rh loadings in the catalysts from 0.05 to 2 wt%. Even after reducing with hydrogen at 900 °C, the average size of Rh particles in the catalysts still remained below 2 nm. The results of catalytic performance evaluation show that CH4 and CO2 conversions of 84% and 90%, respectively, with a H2/CO ratio in syngas close to unity can be achieved with a catalyst of Rh loading of only 0.05 wt% at 750 °C. The performance of the catalyst remains stable for more than 200 h. No significant aggregation of the Rh particles is observed on the catalyst after the reaction. The results of XPS, H2-TPR and O2-TPD characterization methods indicate that the strong interaction between Rh and the γ-Al2O3 nanosheets plays a key role in increasing the dispersion of Rh species in the catalyst and preventing it from sintering under high temperature conditions. This factor is also responsible for the superior activity and stability of the catalyst with extremely low Rh loading for the DRM reaction.Molybdenum disulfide (MoS2) has received widespread attention in recent years due to its exciting properties. However, the practical applications of MoS2 in optoelectronic devices are impeded by the power supply problem, the lack of flexibility, and the low light absorption for planar nanosheets and nanosheet arrays. Inspired by the elaborate architecture of the flower Tagetes erecta L., in this work, a self-assembled divergent MoS2 nanoflower (MoS2_F) with quasi-spherical symmetry is successfully synthesized by a facile one-step hydrothermal method. It is of significance that coupled with asymmetric silver electrodes and packaged by polymethyl methacrylate (PMMA), a self-powered flexible photodetector (PD) based on MoS2_F is actualized and shows an excellent flexible photoresponse performance at zero bias voltage. The divergent structure with quasi-spherical symmetry enables the MoS2_F to achieve strong broadband and omnidirectional absorption (92.7%) and ensures that the MoS2_F maintains the same physical contact on a different bending degree.

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