Morphology is a key parameter in the design of novel nanocrystals and nanomaterials with controlled functional properties. Here, we demonstrate the potential of foreign metal ions to tune the morphology of colloidal semiconductor nanoparticles. We illustrate the underlying mechanism by preparing copper selenide nanocubes in the presence of Al ions. We further characterize the plasmonic properties of the obtained nanocrystals and demonstrate their potential as a platform to produce cubic nanoparticles with different composition by cation exchange.

Chemicals; Copper (I) chloride (reagent grade, 97%), Zinc Oxide (99.9%), 1-octadecene (ODE, 90%), oleic acid (OA, ≥ 99%), hexadecylamine (HDA, tech. 90%) were purchased from Aldrich. Germanium (IV) chloride (99.9999 %) and Selenium (IV) oxide (99.8%) was purshed from Strem. n-Tetradecylphosphonic acid was purchased from PCI Synthesis. Chloroform, isopropanol and ethanol were of analytical grade and obtained from various sources. All chemicals were used as received without further purification.All synthesis were carried out using standard airless techniques: a vacuum/dry argon gas Schlenk line was used for the synthesis and a argon glove-box for storing and handling air and moisture-sensitive chemicals.

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Hydroxyl ionic liquid grafted onto cross-linked divinylbenzene polymer (PDVB-HEIMBr) was fabricated and evaluated as a catalyst for the synthesis of cyclic carbonates from CO 2 and epoxides without the use of any cocatalyst and organic solvent. The catalyst shows good performance across a wide range of epoxides, giving almost quantitative yield of carbonates (140°C, 2.0 MPa of initial CO 2 , and B4 h). The effects of reaction temperature, time and initial CO 2 pressure on product yield were investigated. It is suggested that the synergetic effect between the bromide ions and the hydroxyl groups facilitates the coupling reaction. Furthermore, the PDVBHEIMBr catalyst shows excellent stability and reusability. From the viewpoint of industrial application, the catalyst is very attractive because of its simplicity, activity, stability, and reusability.

Large seasonal water-level fluctuations may influence isotopic signatures of primary producers and the types and amounts of these potential food sources accessible to aquatic fauna of Poyang Lake, the largest freshwater lake in China. In this study, the isotopic signatures of primary producers and consumers were determined, stable carbon and nitrogen isotope analysis and mixing models were combined to investigate the influence of water levels on the diet and isotopic composition of Poyang Lake fish and invertebrates. Five potential food sources (seston, benthic organic matter, aquatic macrophytes, attached algae, and terrestrial plants), 4 species of invertebrates, and 10 species of fish were collected from the lake area during dry and wet seasons between January