![]() We expect this synthetic IV/II-VI epitaxial approach will lead to further studies into the optoelectronic behavior and practical applications of Si and Ge-based nanomaterials. Selected on the basis of their relatively small lattice mismatch compared with crystalline Ge, we explore the growth of epitaxial CdS and ZnS shells using. Thiol ligand exchange easily results in near-infrared active, water-soluble Ge/II-VI nanocrystals. Ge/4.9CdS core/shells show the highest photoluminescence quantum yield and longest radiative recombination lifetime. Ge/II-VI nanocrystals are reproducibly 1-3 orders of magnitude brighter than the brightest Ge cores. The presence of an epitaxial II-VI shell greatly enhances the near-infrared photoluminescence and improves the photoluminescence stability of Ge. In contrast, Ge etching and/or replacement by ZnS result in relatively small Ge/ZnS nanocrystals. Powder X-ray diffraction and electron microscopy techniques, including energy dispersive X-ray spectroscopy and selected area electron diffraction, clearly show the controllable growth of as many as 20 epitaxial monolayers of CdS atop Ge cores. Selected on the basis of their relatively small lattice mismatch compared with crystalline Ge, we explore the growth of epitaxial CdS and ZnS shells using the successive ion layer adsorption and reaction method. To fabricate the coreshell AuCdS nanoparticles-modified ZnO nanowires photoanode, Au nanoparticles were grown on ZnO by chemical reduction of chloroauric acid with sodium citrate, followed by depositing CdS shell on Au nanoparticles via a sequential chemical bath deposition. Here, we use relatively unexplored IV/II-VI epitaxy as a way to enhance the photoluminescence and improve the optical stability of colloidal Ge nanocrystals. Three kinds of nanowires, including multi-walled carbon nanotubes (MWCNTs) coated with CdS nanocrystals (CdS-MWCNTs), and MWCNTs coated with different-thickness CdS sheaths, have been synthesized through mild solution-process synthesis. ![]() Epitaxial growth of a passivating shell is a common strategy employed in the synthesis of highly luminescent II-VI, III-V and IV-VI semiconductor quantum dots. Tuning microwave absorption to meet the harsh requirement of thermal environments is a great challenge. Colloidal Ge nanocrystals are particularly interesting in the development of near-infrared materials for applications in bioimaging, telecommunications and energy conversion. First, the CdS-SV sample (100 mg) was added into 50 mL of deionized (DI) water and sonicated for 20 min. Ge nanocrystals have a large Bohr radius and a small, size-tunable band gap that may engender direct character via strain or doping. Herein, the CdSCsPbBr 3 coreshell microwire (MW) heterojunction was structured via a two-step chemical vapor deposition and was further used to fabricate a UVVis photodetector. CdS-SVCuS (1) coreshell structure photocatalyst was prepared by the sequential cation exchange procedure described in Fig.
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