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. Herein, the appropriate band gap can not only cover the H+ /H 2 and H 2 O 2 /H 2 O potentials, but also inhibit the charge carrier recombination to achieve the overall water splitting 14. Thiol ligand exchange easily results in near-infrared active, water-soluble Ge/II-VI nanocrystals. The CdS 13, with appropriate potential, is reported as a promising overall water splitting photocatalyst. 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. 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 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. 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. demonstrated 7 nm Ge/4.9CdS core/shell nanocrystals that exhibited a PL maximum at 950. 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. The study focused on developing synthetic routes for the colloidal synthesis of ZnSe/CdS semiconductor heterostructures, various in size and geometry, and. Ge-based nanomaterials, such as GeSn, GeTe, GeSe, GeS, and Ge/Cds and GeSn/CdS core/shell nanocrystals, many of which are useful for applications in. The maximal fluorescence wavelengths of L-cysteine-coated CdSe/CdS QDs are 585 nm. The absorption spectra and fluorescence spectra of L-cysteine-coated CdSe/CdS QDs were obtained and shown in Fig. Colloidal Ge nanocrystals are particularly interesting in the development of near-infrared materials for applications in bioimaging, telecommunications and energy conversion. L-Cysteine-coated CdSe/CdS QDs were dissolved in PBS (0.1 M, pH 7.4). ![]() Ge nanocrystals have a large Bohr radius and a small, size-tunable band gap that may engender direct character via strain or doping.
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