硫?qū)俳t外納米晶的水相合成、表征及其應(yīng)用
發(fā)布時(shí)間：2018-08-02 09:40
【摘要】：近紅外發(fā)光的半導(dǎo)體納米晶具有許多優(yōu)異的光電特性,使得它們?cè)诠怆娖骷�、光纖通訊和生物醫(yī)學(xué)等領(lǐng)域具有潛在的應(yīng)用價(jià)值和廣闊的應(yīng)用前景。迄今為止,高質(zhì)量的近紅外發(fā)光納米晶往往通過(guò)有機(jī)路線合成,水相合成高熒光近紅外發(fā)光材料研究較少。雖然汞硫?qū)偌{米材料是一類性能優(yōu)良的近紅外發(fā)光材料,但是合成的HgS納米晶發(fā)光性能極弱,光熱穩(wěn)定性較差。本論文主要集中研究了近紅外發(fā)光HgS納米晶的水相合成;開(kāi)發(fā)了基于HgS納米晶高熒光、穩(wěn)定的Cd:HgS/CdS納米晶和HgS/ZnS核殼結(jié)構(gòu)納米材料,并且展現(xiàn)了它們?cè)诠怆姾蜕锍上裆系膽?yīng)用;另外,一鍋法合成了谷胱甘肽穩(wěn)定的高熒光的近紅外Ag2S納米晶,并將HgS/ZnS核殼納米晶首次作為熒光探針檢測(cè)微量Cu~(2+)離子。研究工作主要包括以下五個(gè)方面的內(nèi)容:1.谷脫甘肽穩(wěn)定的近紅外發(fā)射的β-HgS納米晶的水相合成與表征本文發(fā)展了一種簡(jiǎn)單,快速和綠色的室溫水相合成路線首次合成了近紅外發(fā)光的谷胱甘肽穩(wěn)定的β-HgS納米晶。所制備的HgS納米晶具有立方晶型,熒光發(fā)射峰位在近紅外775 nm到1044 nm波長(zhǎng)范圍內(nèi)可調(diào),表現(xiàn)了良好的量子限域效應(yīng)。與文獻(xiàn)所報(bào)道的HgS納米晶相比,我們所制備的谷胱甘肽穩(wěn)定的HgS納米晶發(fā)光效率大大提高,最大量子效率可達(dá)2.8%;同時(shí)HgS納米晶溶液穩(wěn)定性也得到很大改善,4 ℃冰箱放置4個(gè)月后,HgS納米晶的熒光發(fā)射峰僅移動(dòng)了 9nm,室溫放置7天后,熒光發(fā)射峰也僅移動(dòng)了 23 nm。FT-IR譜表明HgS納米晶所呈現(xiàn)的高的穩(wěn)定性得益于谷胱甘肽(GSH)分子與納米晶表面Hg原子之間的多重配位作用。所制備的谷胱甘肽穩(wěn)定的β-HgS納米晶發(fā)光波段位于近紅外區(qū),對(duì)已報(bào)道的可見(jiàn)光(400-800 nm)和紅外光(1000-1600 nm)發(fā)射的HgS納米晶是一個(gè)有益補(bǔ)充,賦予了 HgS這一材料更多潛在的應(yīng)用價(jià)值。2.Cd~(2+)調(diào)控的高熒光近紅外發(fā)射HgS納米晶的合成及其光學(xué)應(yīng)用體相HgS材料是一種科技上非常重要的材料,然而HgS納米晶弱的熒光發(fā)射及其差的穩(wěn)定性嚴(yán)重阻礙了該材料的潛在應(yīng)用價(jià)值。目前,對(duì)HgS納米晶而言,最突出的問(wèn)題就是它的不可控生長(zhǎng)以及對(duì)環(huán)境影響敏感的本征表面態(tài)。本研究中,我們通過(guò)Cd~(2+)離子調(diào)控的方法解決了上述問(wèn)題,首次制備出了穩(wěn)定的高熒光的Cd:HgS/CdS納米晶,有效了調(diào)控了 HgS納米晶的帶隙水平,使得其本征表面態(tài)遠(yuǎn)離表面,明顯降低了周圍環(huán)境和納米晶表面態(tài)的相互作用,大幅提高了激子躍遷。與"裸露"的HgS納米晶相比,所制備的Cd:HgS/CdS納米晶的熒光峰在724 nm～825 nm之間連續(xù)可調(diào),最大室溫量子產(chǎn)率高達(dá)40%,最大半峰寬為95 nm。透射電鏡(TEM),X-射線粉末衍射技術(shù)(XRD),X-射線光電子能譜(XPS)和原子吸收法(AAS)表征了 Cd:HgS/CdS納米晶的結(jié)構(gòu),形貌和元素組成。所制備的Cd調(diào)控的HgS納米晶具有立方晶型結(jié)構(gòu),由同質(zhì)的HgCdS合金包被一層薄的CdS殼層組成。進(jìn)而,我們對(duì)Cd:HgS/CdS納米晶獨(dú)特的形成機(jī)理進(jìn)行了探討。這種新合成的高熒光穩(wěn)定的近紅外發(fā)射的Cd:HgS/CdS NCs極大擴(kuò)展了基于HgS納米晶的應(yīng)用價(jià)值,可直接作為一種防偽用的熒光墨水,也可涂布于藍(lán)光LED表面作為一種優(yōu)良的光轉(zhuǎn)化器。3.超亮、低毒性近紅外發(fā)射的HgS/ZnS納米晶的合成及其生物成像研究迄今為止,高質(zhì)量的近紅外發(fā)光納米晶往往通過(guò)有機(jī)路線合成,水溶性高熒光的近紅外發(fā)光材料較少。汞硫?qū)偌{米材料雖然是一類優(yōu)良的近紅外發(fā)光的材料,但是Hg元素的潛在毒性限制了它們的多樣應(yīng)用前景。本研究中我們通過(guò)水相合成方法首次設(shè)計(jì)合成了一種低毒性的,高熒光穩(wěn)定的HgS/ZnS核殼結(jié)構(gòu)納米材料。TEM,XRD和XPS表明了 ZnS殼的生成。在HgS納米晶表面外延生長(zhǎng)一層ZnS殼層后,弱發(fā)射的HgS納米晶轉(zhuǎn)化成了超亮的HgS/ZnS納米晶,量子產(chǎn)率高達(dá)43.8%,并且隨著反應(yīng)pH值的不同HgS/ZnS納米晶的發(fā)射峰位可在785 nm到1063 nm連續(xù)可調(diào)。重要的是,體外細(xì)胞毒性實(shí)驗(yàn)明顯表明HgS/ZnS納米晶具有優(yōu)異的生物相容性,在其孵育濃度高達(dá)150 μg·L-1時(shí),細(xì)胞存活率仍維持在80%以上,與低毒性Ag2S納米晶的生物相容性相當(dāng)。更為重要的是,實(shí)驗(yàn)證實(shí)低毒性高熒光的HgS/ZnS納米晶是一種優(yōu)異的熒光探針,適用于體外和體內(nèi)成像。應(yīng)用于裸鼠活體成像時(shí),組織穿透深度達(dá)到2 cm,納米晶的熒光與機(jī)體自發(fā)熒光有著明顯的波長(zhǎng)區(qū)別,具有優(yōu)異的對(duì)比度。這一新型的超亮的HgS/ZnS納米晶對(duì)生物醫(yī)學(xué)領(lǐng)域高靈敏度、高分辨率和多色成像提供了新的契機(jī)。4.谷腕甘肽穩(wěn)定的近紅外發(fā)射的Ag2S納米晶的水相合成與表征本研究采用谷胱甘肽作為穩(wěn)定劑、AgNO3作為Ag前驅(qū)體、硫代乙酰胺(TAA)作硫源,制備了穩(wěn)定的水溶性近紅外Ag2S納米晶,并且系統(tǒng)地研究了硫源、單體濃度、Ag/S比、反應(yīng)溫度及時(shí)間以及配體等合成條件對(duì)此近紅外Ag2S納米晶熒光特性的影響。結(jié)果表明,采用TAA作為硫源,GSH作為配體,[Ag+]=2 mM,Ag:GSH:S=1:2.5:0.25時(shí),在pH=8的條件下,70 ℃加熱30 min得到Ag2S納米晶熒光強(qiáng)度最強(qiáng)且熒光峰形對(duì)稱。熒光光譜表征顯示此Ag2S納米晶熒光發(fā)射波長(zhǎng)為915 nm,量子產(chǎn)率高達(dá)4.5%,比文獻(xiàn)所報(bào)道的發(fā)光效率顯著提高。粉末X射線衍射和透射電子顯微鏡表征顯示此Ag2S納米晶為單斜晶系a-Ag2S,尺寸大小約為5 nm。這種合成方法簡(jiǎn)單廉價(jià),所得到的水溶性近紅外Ag2S納米晶無(wú)需經(jīng)過(guò)相轉(zhuǎn)移即可直接應(yīng)用于生命體系,具有優(yōu)異的生物相容性,在細(xì)胞組織成像等領(lǐng)域有著巨大的應(yīng)用前景。5.高熒光近紅外HgS/ZnS核殼納米晶作為銅離子的熒光探針首次水相成功合成了谷胱甘肽穩(wěn)定的HgS/ZnS核殼納米晶,研究了其與Cu~(2+)的相互作用。實(shí)驗(yàn)中觀察到,HgS/ZnS核殼納米晶的熒光能被Cu~(2+)顯著猝滅,從而建立了一種測(cè)定Cu~(2+)的新方法。干擾實(shí)驗(yàn)表明,干擾離子對(duì)微量銅的檢測(cè)幾乎沒(méi)有干擾。在最優(yōu)化的條件下,納米晶的熒光強(qiáng)度與Cu24+的濃度在0.125～12.5μmolL-1范圍內(nèi)呈現(xiàn)良好的線性關(guān)系,其檢測(cè)限為0.07μmolL-1。本法提出測(cè)定Cu~(2+)的方法具有線性范圍寬、靈敏度高、方法簡(jiǎn)單等特點(diǎn),適用于實(shí)際樣品中微量Cu~(2+)的測(cè)定,展現(xiàn)了高熒光近紅外發(fā)射的HgS/ZnS納米晶在分析領(lǐng)域的應(yīng)用前景。
[Abstract]:The near infrared luminescent semiconductor nanocrystals have many excellent photoelectric properties, which make them have potential applications and broad applications in the fields of optoelectronic devices, optical fiber communication and biomedicine. So far, high quality near infrared luminescent nanocrystals are often synthesized by organic route, and high fluorescence near infrared hair is synthesized by water phase synthesis. There are few studies on optical materials. Although Hg and s nanomaterials are a kind of near infrared luminescent materials with excellent properties, the luminescent properties of the synthesized HgS nanocrystals are very weak and the thermal stability is poor. This paper mainly focuses on the study of the water phase synthesis of near infrared luminescent HgS nanocrystals, and the high fluorescence and stable Cd:HgS/CdS nanocrystals based on HgS nanocrystals have been developed. The nanomaterials of crystal and HgS/ZnS nuclear shell structure and their applications on Photoelectrical and biological imaging; in addition, one pot method has been used to synthesize the stable and high fluorescence near infrared Ag2S nanocrystals of glutathione, and the HgS/ZnS nuclear shell nanocrystals for the first time as a fluorescence probe to detect the trace Cu~ (2+) ions. The research work mainly includes the following five aspects Content: water phase synthesis and characterization of 1. Valley DEG stable near infrared emission of beta -HgS nanocrystals. This paper developed a simple, fast and green chamber warm water phase synthesis route for the first time to synthesize the near infrared luminescent glutathione stable beta -HgS nanocrystals. The prepared HgS nanocrystals have cubic crystal type and the fluorescence emission peak is near. The infrared 775 nm to 1044 nm wavelengths are adjustable, showing a good quantum confinement effect. Compared with the HgS nanocrystals reported in the literature, the luminescence efficiency of the glutathione stable HgS nanocrystals is greatly improved, the maximum quantum efficiency is up to 2.8%, and the stability of HgS nanocrystalline solution is greatly improved, and the refrigerator is placed at 4 degrees centigrade 4. After a month, the fluorescence emission peak of HgS nanocrystals moved only 9nm. After 7 days at room temperature, the fluorescence emission peak was only moved by 23 nm.FT-IR spectra, indicating that the high stability of the HgS nanocrystals was due to the multiple coordination between the glutathione (GSH) molecule and the nanocrystalline surface Hg atom. The glutathione stable beta -HgS nano was prepared. The crystal luminescence band is located in the near infrared region. It is a beneficial supplement to the reported HgS nanocrystals emitted by the visible light (400-800 nm) and infrared light (1000-1600 nm). It gives HgS this material more potential application value.2.Cd~ (2+) regulated by high fluorescence near infrared emission HgS nanocrystalline crystal and its optical application body phase HgS material It is a very important material in science and technology, however, the weak fluorescence emission of HgS nanocrystalline and its poor stability have seriously hindered the potential application of this material. At present, the most prominent problem for HgS nanocrystals is its uncontrollable growth and the intrinsic surface state sensitive to the environmental impact. In this study, we use Cd~ (2+) ion regulation. The method solved the above problem. The stable high fluorescence Cd:HgS/CdS nanocrystalline was prepared for the first time. The band gap level of HgS nanocrystalline was controlled effectively. The intrinsic surface state was far away from the surface, and the interaction between the surrounding environment and the nanocrystalline surface state was obviously reduced, and the exciton transition was greatly improved. Compared with the bare HgS nanocrystals, The fluorescence peaks of the prepared Cd:HgS/CdS nanocrystals are continuously adjustable from 724 nm to 825 nm, the maximum room temperature quantum yield is up to 40%, the maximum half peak width is 95 nm. transmission electron microscopy (TEM), X- ray powder diffraction (XRD), X- ray photoelectron spectroscopy (XPS) and atomic absorption spectrometry (AAS) characterizing the structure, morphology and element composition of the Cd:HgS/CdS nanocrystals. The HgS nanocrystals prepared by Cd have cubic crystal structure and are composed of a thin CdS shell with homogenous HgCdS alloy package. Then, we discuss the unique formation mechanism of Cd:HgS/CdS nanocrystals. This newly synthesized highly stable near infrared emission Cd:HgS/ CdS NCs greatly extends the HgS nanocrystals. Using value, it can be directly used as a kind of anti-counterfeit fluorescent ink, and can also be coated on the surface of blue light LED as an excellent optical converter.3. super bright, low toxic near infrared emission of HgS/ZnS nanocrystals and bioimaging studies. High quality near infrared luminescent nanocrystals are often synthesized by organic route and high water solubility. There are few near infrared luminescent materials. Although mercury sulfide nanomaterials are excellent near infrared luminescence materials, the potential toxicity of Hg elements limits their application prospects. In this study, we first designed and synthesized a low toxic, highly fluorescent stable HgS/ZnS nuclear shell nanostructure by water phase synthesis. The materials.TEM, XRD and XPS show the formation of ZnS shells. After the epitaxial growth of a ZnS shell on the HgS nanocrystalline surface, the weakly emitted HgS nanocrystals are converted to ultra bright HgS/ZnS nanocrystals with a quantum yield of up to 43.8%, and the emission peaks of the HgS/ZnS nanocrystals can be continuously adjustable from 785 nm to 1063 with the pH value of the reaction pH. Important is the body. The external cytotoxicity test showed that the HgS/ZnS nanocrystals had excellent biocompatibility. When the incubation concentration was up to 150 g. L-1, the cell survival rate remained above 80%, and the biocompatibility of the low toxic Ag2S nanocrystals was equal. The experiment proved that the HgS/ZnS nanocrystals of low toxic Gao Yingguang were a kind of excellent fluorescence. The probe is suitable for in vitro and in vivo imaging. In vivo imaging of nude mice, the tissue penetration depth is up to 2 cm. The fluorescence of nanocrystalline has obvious wavelength difference with the body spontaneous fluorescence, and has excellent contrast. This new super bright HgS/ZnS nanocrystalline provides high sensitivity, high resolution and polychromatic imaging in the field of biomedicine A new opportunity for the water phase synthesis and characterization of Ag2S nanocrystalline with stable near infrared emission of.4. Valley carpi, this study uses glutathione as a stabilizer, AgNO3 as a precursor of Ag and thioacetamide (TAA) as the sulfur source, to prepare a stable water-soluble near infrared Ag2S nanocrystalline, and systematically studies the sulfur source, monomer concentration, Ag/S ratio, and reaction. The effects of temperature, time and ligands on the fluorescence characteristics of the near infrared Ag2S nanocrystals show that TAA is used as a sulfur source, GSH as a ligand, [Ag+]=2 mM, Ag:GSH:S=1:2.5:0.25, at pH=8, and the fluorescence intensity of Ag2S nanocrystalline is the strongest and the fluorescence peak symmetry is obtained at 70 C under the condition of pH=8. The fluorescence spectrum characterization shows that The fluorescence emission wavelength of this Ag2S nanocrystalline is 915 nm, the quantum yield is up to 4.5%, which is significantly higher than that reported in the literature. Powder X ray diffraction and transmission electron microscopy show that the Ag2S nanocrystalline is monoclinic a-Ag2S and the size is about 5 nm.. The synthesis method is simple and cheap, and the water-soluble near infrared Ag2S Nana is obtained. It can be applied directly to the life system without phase transfer. It has excellent biocompatibility and has great potential application in the field of cell tissue imaging..5. high fluorescence near infrared HgS/ZnS nuclear shell nanocrystals have successfully synthesized the stable HgS/ZnS nuclear shell nanocrystals of glutathione by the first aqueous phase of copper ion. The interaction with Cu~ (2+) was observed in the experiment. It was observed in the experiment that the fluorescence energy of the HgS/ZnS nucleation nanocrystals was quenched by Cu~ (2+), thus a new method for determining Cu~ (2+) was established. The interference experiment showed that the interference ions had little interference to the detection of trace copper. Under the optimal conditions, the fluorescence intensity of the nanocrystalline and the concentration of Cu24+ was 0.12 There is a good linear relationship within the range of 5 ~ 12.5 molL-1. The detection limit is 0.07 mu molL-1.. The method proposed for the determination of Cu~ (2+) has the characteristics of wide linear range, high sensitivity and simple method. It is suitable for the determination of trace Cu~ (2+) in the actual samples and shows the application of the Gao Yingguang nanocrystalline in the analysis field of the near infrared emission of Gao Yingguang. View.
【學(xué)位授予單位】：南京大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB383.1
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本文編號(hào)：2159024
[Abstract]:The near infrared luminescent semiconductor nanocrystals have many excellent photoelectric properties, which make them have potential applications and broad applications in the fields of optoelectronic devices, optical fiber communication and biomedicine. So far, high quality near infrared luminescent nanocrystals are often synthesized by organic route, and high fluorescence near infrared hair is synthesized by water phase synthesis. There are few studies on optical materials. Although Hg and s nanomaterials are a kind of near infrared luminescent materials with excellent properties, the luminescent properties of the synthesized HgS nanocrystals are very weak and the thermal stability is poor. This paper mainly focuses on the study of the water phase synthesis of near infrared luminescent HgS nanocrystals, and the high fluorescence and stable Cd:HgS/CdS nanocrystals based on HgS nanocrystals have been developed. The nanomaterials of crystal and HgS/ZnS nuclear shell structure and their applications on Photoelectrical and biological imaging; in addition, one pot method has been used to synthesize the stable and high fluorescence near infrared Ag2S nanocrystals of glutathione, and the HgS/ZnS nuclear shell nanocrystals for the first time as a fluorescence probe to detect the trace Cu~ (2+) ions. The research work mainly includes the following five aspects Content: water phase synthesis and characterization of 1. Valley DEG stable near infrared emission of beta -HgS nanocrystals. This paper developed a simple, fast and green chamber warm water phase synthesis route for the first time to synthesize the near infrared luminescent glutathione stable beta -HgS nanocrystals. The prepared HgS nanocrystals have cubic crystal type and the fluorescence emission peak is near. The infrared 775 nm to 1044 nm wavelengths are adjustable, showing a good quantum confinement effect. Compared with the HgS nanocrystals reported in the literature, the luminescence efficiency of the glutathione stable HgS nanocrystals is greatly improved, the maximum quantum efficiency is up to 2.8%, and the stability of HgS nanocrystalline solution is greatly improved, and the refrigerator is placed at 4 degrees centigrade 4. After a month, the fluorescence emission peak of HgS nanocrystals moved only 9nm. After 7 days at room temperature, the fluorescence emission peak was only moved by 23 nm.FT-IR spectra, indicating that the high stability of the HgS nanocrystals was due to the multiple coordination between the glutathione (GSH) molecule and the nanocrystalline surface Hg atom. The glutathione stable beta -HgS nano was prepared. The crystal luminescence band is located in the near infrared region. It is a beneficial supplement to the reported HgS nanocrystals emitted by the visible light (400-800 nm) and infrared light (1000-1600 nm). It gives HgS this material more potential application value.2.Cd~ (2+) regulated by high fluorescence near infrared emission HgS nanocrystalline crystal and its optical application body phase HgS material It is a very important material in science and technology, however, the weak fluorescence emission of HgS nanocrystalline and its poor stability have seriously hindered the potential application of this material. At present, the most prominent problem for HgS nanocrystals is its uncontrollable growth and the intrinsic surface state sensitive to the environmental impact. In this study, we use Cd~ (2+) ion regulation. The method solved the above problem. The stable high fluorescence Cd:HgS/CdS nanocrystalline was prepared for the first time. The band gap level of HgS nanocrystalline was controlled effectively. The intrinsic surface state was far away from the surface, and the interaction between the surrounding environment and the nanocrystalline surface state was obviously reduced, and the exciton transition was greatly improved. Compared with the bare HgS nanocrystals, The fluorescence peaks of the prepared Cd:HgS/CdS nanocrystals are continuously adjustable from 724 nm to 825 nm, the maximum room temperature quantum yield is up to 40%, the maximum half peak width is 95 nm. transmission electron microscopy (TEM), X- ray powder diffraction (XRD), X- ray photoelectron spectroscopy (XPS) and atomic absorption spectrometry (AAS) characterizing the structure, morphology and element composition of the Cd:HgS/CdS nanocrystals. The HgS nanocrystals prepared by Cd have cubic crystal structure and are composed of a thin CdS shell with homogenous HgCdS alloy package. Then, we discuss the unique formation mechanism of Cd:HgS/CdS nanocrystals. This newly synthesized highly stable near infrared emission Cd:HgS/ CdS NCs greatly extends the HgS nanocrystals. Using value, it can be directly used as a kind of anti-counterfeit fluorescent ink, and can also be coated on the surface of blue light LED as an excellent optical converter.3. super bright, low toxic near infrared emission of HgS/ZnS nanocrystals and bioimaging studies. High quality near infrared luminescent nanocrystals are often synthesized by organic route and high water solubility. There are few near infrared luminescent materials. Although mercury sulfide nanomaterials are excellent near infrared luminescence materials, the potential toxicity of Hg elements limits their application prospects. In this study, we first designed and synthesized a low toxic, highly fluorescent stable HgS/ZnS nuclear shell nanostructure by water phase synthesis. The materials.TEM, XRD and XPS show the formation of ZnS shells. After the epitaxial growth of a ZnS shell on the HgS nanocrystalline surface, the weakly emitted HgS nanocrystals are converted to ultra bright HgS/ZnS nanocrystals with a quantum yield of up to 43.8%, and the emission peaks of the HgS/ZnS nanocrystals can be continuously adjustable from 785 nm to 1063 with the pH value of the reaction pH. Important is the body. The external cytotoxicity test showed that the HgS/ZnS nanocrystals had excellent biocompatibility. When the incubation concentration was up to 150 g. L-1, the cell survival rate remained above 80%, and the biocompatibility of the low toxic Ag2S nanocrystals was equal. The experiment proved that the HgS/ZnS nanocrystals of low toxic Gao Yingguang were a kind of excellent fluorescence. The probe is suitable for in vitro and in vivo imaging. In vivo imaging of nude mice, the tissue penetration depth is up to 2 cm. The fluorescence of nanocrystalline has obvious wavelength difference with the body spontaneous fluorescence, and has excellent contrast. This new super bright HgS/ZnS nanocrystalline provides high sensitivity, high resolution and polychromatic imaging in the field of biomedicine A new opportunity for the water phase synthesis and characterization of Ag2S nanocrystalline with stable near infrared emission of.4. Valley carpi, this study uses glutathione as a stabilizer, AgNO3 as a precursor of Ag and thioacetamide (TAA) as the sulfur source, to prepare a stable water-soluble near infrared Ag2S nanocrystalline, and systematically studies the sulfur source, monomer concentration, Ag/S ratio, and reaction. The effects of temperature, time and ligands on the fluorescence characteristics of the near infrared Ag2S nanocrystals show that TAA is used as a sulfur source, GSH as a ligand, [Ag+]=2 mM, Ag:GSH:S=1:2.5:0.25, at pH=8, and the fluorescence intensity of Ag2S nanocrystalline is the strongest and the fluorescence peak symmetry is obtained at 70 C under the condition of pH=8. The fluorescence spectrum characterization shows that The fluorescence emission wavelength of this Ag2S nanocrystalline is 915 nm, the quantum yield is up to 4.5%, which is significantly higher than that reported in the literature. Powder X ray diffraction and transmission electron microscopy show that the Ag2S nanocrystalline is monoclinic a-Ag2S and the size is about 5 nm.. The synthesis method is simple and cheap, and the water-soluble near infrared Ag2S Nana is obtained. It can be applied directly to the life system without phase transfer. It has excellent biocompatibility and has great potential application in the field of cell tissue imaging..5. high fluorescence near infrared HgS/ZnS nuclear shell nanocrystals have successfully synthesized the stable HgS/ZnS nuclear shell nanocrystals of glutathione by the first aqueous phase of copper ion. The interaction with Cu~ (2+) was observed in the experiment. It was observed in the experiment that the fluorescence energy of the HgS/ZnS nucleation nanocrystals was quenched by Cu~ (2+), thus a new method for determining Cu~ (2+) was established. The interference experiment showed that the interference ions had little interference to the detection of trace copper. Under the optimal conditions, the fluorescence intensity of the nanocrystalline and the concentration of Cu24+ was 0.12 There is a good linear relationship within the range of 5 ~ 12.5 molL-1. The detection limit is 0.07 mu molL-1.. The method proposed for the determination of Cu~ (2+) has the characteristics of wide linear range, high sensitivity and simple method. It is suitable for the determination of trace Cu~ (2+) in the actual samples and shows the application of the Gao Yingguang nanocrystalline in the analysis field of the near infrared emission of Gao Yingguang. View.
【學(xué)位授予單位】：南京大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB383.1
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本文編號(hào)：2159024
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