Water-soluble Fluorescent Germanium Nanomaterials: Synthesis, Characterization And Applications

Germanium?Ge?nanomaterials have attracted much attention recently for their valuable semiconducting,special optical properties,and the potential applications in optoelectronic devices,bio-imaging and energy conversion and storage areas.Most of synthetize strategies rely on high reaction temperatures,toxic precursors and complex reaction process,which brings greater trouble to further applications.Therefore,the study of synthetic route and the development of application in the biomedical field are needed.The research approachs are showed as follows:1.Water-soluble germanium-doped cadmium sulfide quantum dots?Ge:CdS d-dots?were successfully synthesized by a facile one-pot method,and used as fluorescent probes for labeling live MCF-7 cells.The optical properties of the q-dots and several key parameters of the synthesis conditions were studied,and the mechanism of these parameters was also discussed.After doping with germanium,the PL intensity increased 50%,while improving the photostability and fluorescence quantum yield.Furthermore,the toxicity of CdS quantum dot decreased after doping with germanium duo to its low toxicity,which greatly improved the CdS quantum dots biocompatibility.Then the doped quantum dots modified with folic acid?FA?to use as fluorescent probes,which expanded the application of semiconductor quantum dots in the biomedical field.2.Cu doped GeS?Cu:GeS?were synthesized via a one-pot noninjection synthetic approach by hydrothermal treatment inorganic salts without using any organic solvents.The resulting Cu:GeSshowCu²⁺-content-dependentintensityandemission-peakwavelength photoluminescence?PL?emission with the high PL quantum yield?QY?up to 15.6%.The tunable emission from 430 to 520 nm evidences the successful doping of Cu into GeS.The doped nanocrystals are characterized by XRD,TEM and Raman spectroscopy techniques to reveal their crystal structure.In addition,the Cu:GeS show highly photo stability,which is important for its future application in many fields.3.A facile method is developed to synthesize fluorescent emission tunable Germanium/Carbon?Ge/C?Nanostructures regulated by phosphate through hydrothermal treatment.The fluorescence emission of the Ge/C Nanostructures thus produced is tunable by simply adjusting the concentration of monopotassium phosphate?KH₂PO₄?.The Ge/C Nanostructures show an emission with a KH₂PO₄-content-dependent intensity and emission-peak wavelength.Moerover,the as-obtained Ge/C Nanostructures exhibit bright photoluminescent property,low toxicity,and high stability against photobleaching.Imaging of MCF-7 cells was observed with high resolution using Ge/C Nanostructures as probes and validates their use in imaging applications and their multicolor property in the living cell system.