A Mechanochemical Route for ZnS Nanocrystals, and Batch Sorting along Size Distribution

Abstract

The assistances of sodium dodecyl benzene sulfonate (SDBS) and aging treatment were introduced to further improve the room-temperature mechanochemical synthesis of the quantum-sized zinc sulfide (ZnS) nanocrystals. As a result, a green strategy for synthesizing the monodisperse nanocrystals with tunable size and crystallinity was developed, holding convenient, highly efficient and low pollution. Size evolution shows a gradually increasing trend along the aging-temperature. A model that the independent reaction cells constructed by SDBS-wrapped reactant packages (solid state vesicles, SSVs) for the confined growth of ZnS nanocrystals was proposed to access the formation mechanism of ZnS quantized crystal in a solid-state synthesis system. The band gaps and band-edge luminescent emissions of as-prepared ZnS nanocrystals experienced the size-dependent quantum confinement effect, while the trap-state emissions exhibited the lattice integrity-dependence. Furthermore, ZnS quantum-sized nanocrystals with narrower size distribution can be obtained by a batch-sorting process through adjusting the centrifugal speed.

Photoresponse of CdSe-PVA nanocomposite films at low magnetic fields

“…It can also be noticed that R increased with increasing H (till 1000 G) at any value of I L . As can be observed in figure 8(d), the R of Sample B monotonically decreased with I L at any value The CdSe-PVA nanocomposite films are expected to show the photoresistor behavior (decreasing R with increasing I L ) [82][83][84][85]. In dark, a photoresistor can have R as high as several M.Ω, while in the light, the R will be reduced to much lower values.…”

Sulfur deficiency mediated visible emission of ZnS QDs by magnesium dopant and their application in waste water treatment

“…Additionally, violet and blue emissions at 428 nm and 479 nm, respectively, are caused by sulfur-related point defects in the ZnS lattice [ 13 ]. The emission centered at 428 nm corresponding to the transition of electron from conduction band interstitial sulfur and emission at 479 nm attributed to recombination at sulfur vacancy sites [ 42 ]. The spectra indicate that the luminescence is significantly enhanced with 10% Mg doping, while further increases in Mg concentration do not show a significant increase in luminescence intensity.…”

Solvent-Free Mechanochemical Synthesis and Characterization of Nickel Tellurides with Various Stoichiometries: NiTe, NiTe2 and Ni2Te3

“…Our group earlier reported on the mechanochemical synthesis of copper and cadmium chalcogenides (CuS, CuSe 2 , Cu 7 Te 5 , CdS, CdSe, and CdTe) [ 41 ] as well as mechanochemical preparation of Al 2 S 3 , Al 2 Se 3 , Ga 2 S 3 , and Ga 2 Se 3 [ 42 ]. More recently, syntheses of copper-nickel antimony sulfide [ 43 ]; lead bismuth telluride [ 44 ]; zinc sulfide [ 45 ]; and silver, indium, and gallium selenides [ 46 ] using the mechanochemical approach have been reported. After a thorough search, we found only one paper reported the preparation of nickel tellurides by mechanical alloying: Campos prepared NiTe nanocrystals by milling a stoichiometric mixture of elemental Ni and Te powders in an argon atmosphere for 3 h–10 h [ 47 ].…”