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Abstract: A two-step colloidal synthesis of highly uniform Ag2S–ZnS matchstick-like hetero-nanorods, composed of Ag2S head and ZnS rod-like stem, is reported. Dodecanethiol is used as a sulfur source and a solvent. Ag2S nanocrystals are first prepared, act as a catalyst to grow anisotropic ZnS nanorods, and finally remain at the tip of the resultant nanorods, leading to Ag2S–ZnS hetero-nanorods with a matchstick-like shape. By decreasing the amount of Ag precursor (AgNO3), uniform ZnS nanorods without Ag2S catalytic heads can be prepared. The disappearance of Ag2S heads is attributed to the diffusion of Ag+ ions from Ag2S into the growing ZnS nanorods. These hetero-nanorods combine narrow band gap semiconductor Ag2S (bulk E g =0.9–1.1eV) with wide band gap semiconductor ZnS (bulk E g =3.77eV) and may be promising optical and/or optoelectronic materials. [Copyright &y& Elsevier]

Abstract: CdS hexagonal nanoplates were prepared by a seeded growth mechanism in a one-pot solvothermal synthesis, where CuS was precipitated from solution before CdS and subsequently acted as the preformed seeds due to its relatively low solubility product constant (K sp) compared to CdS. The morphology, crystal structure and optical property of the as-prepared nanoplates were characterized by XRD, TEM, HRTEM, EDS, Raman and UV–vis absorption spectra. Our results showed both CdS and CuS crystallized in the hexagonal structure and that they had good matches with each other in the crystal planes of both {100} and {101}. The formation of CdS hexagonal nanoplates was attributed to the heteroepitaxial growth of CdS on CuS seeds at the highly reactive {100} and {101} crystal planes. [Copyright &y& Elsevier]

Abstract: ZnSe nanowires with a high aspect ratio were synthesized via a solution-phase catalytic growth route, in which Ag2Se seeds served as catalysts and oleylamine (OA) as a surfactant. The strong capping/reducing capability of OA effectively decreased the size of Ag2Se catalytic seeds and thus the diameter of ZnSe nanowires with an improved uniformity. Other surfactants such as polyvinyl pyrrolidone (PVP) and citric acid (CA) were further comparably used in the synthesis, leading to the difference in the diameter and diameter-distribution of ZnSe nanowires. Meanwhile, the UV–vis absorption and Raman spectra of ZnSe nanowires were investigated, indicating a high quality of the resultant nanowires. [Copyright &y& Elsevier]

• Al/Mg-Li/Al composite plate with a flat interface. • Expanded the conventional frequency band from 30 to 1500 MHz to 30–6000 MHz. • SE of Al/Mg-Li/Al composite plate was enhanced by adjusting different thickness ratios. Magnesium alloy has good electromagnetic shielding performance, but its shielding effectiveness on high-frequency electromagnetic waves is weak. In order to solve the above problems, aluminum, which is also a lightweight material, is covered on top of Mg. The feasibility of this method is demonstrated by microstructure analysis and measurement of conductivity and electromagnetic shielding effect, and the results show that the Al/Mg-Li/Al-X sandwich structure is improved by nearly 10 dB at 6000 MHz, and the improvement of electromagnetic shielding efficiency is attributed to the absorption loss caused by the addition of Al layer and the reflection loss at the interlayer interfaces. In addition, the alternating arrangement of α-Mg/β-Li in the Mg layer, and the interfaces formed by the Mg 12 YZn hard phase particles and the matrix phase also contribute to the electromagnetic shielding efficiency. [ABSTRACT FROM AUTHOR]

Novel visible-light-active carbon-doped graphitic carbon nitride composites (C/g-C 3 N 4 ) were prepared by hydrothermal treatment of the mixture of g-C 3 N 4 and glucose solution. The products were characterized by X-ray diffraction, transmission electron microscopy (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflection spectroscopy (UV–vis), and photocurrent–time measurement (PT). Compared to g-C 3 N 4 , the C/g-C 3 N 4 showed enhanced visible-light absorption, adsorptivity and improved photocurrent response. C/g-C 3 N 4 composites also showed enhanced performance for Methylene Blue (MB) photodegradation. The enhanced activity of the C/g-C 3 N 4 composites is attributed to the synergistic effect between the doped carbon and g-C 3 N 4 . [ABSTRACT FROM AUTHOR]