本文選題：石墨烯　切入點：色氨酸　出處：《西北師范大學(xué)》2015年碩士論文

【摘要】：石墨烯是碳原子以sp~2雜化形成的單層二維納米材料。由于它具有高的導(dǎo)電性,大的比表面積,低廉的制備成本等使其成為一種理想的電化學(xué)材料。然而,石墨烯是疏水性的,在溶液中的分散性較差,而且石墨烯片層之間的范德華力和強烈的π-π堆疊作用使其趨于不可逆轉(zhuǎn)的凝聚,甚至是重新堆疊為石墨,這些都限制了石墨烯的進(jìn)一步應(yīng)用。對石墨烯進(jìn)行功能化,提高石墨烯在溶液中的分散性,是目前對于石墨烯材料應(yīng)用的最主要的方法。本論文基于石墨烯的特性,利用色氨酸分子通過π-π作用功能化石墨烯,改善其分散性,提高電催化性能。將色氨酸功能化石墨烯修飾在電極表面,構(gòu)建相應(yīng)的傳感器,用于抗壞血酸、多巴胺、尿酸的分別或同時檢測,然后電沉積金納米在色氨酸功能化石墨烯上,利用它們之間的協(xié)同作用,進(jìn)一步提高電催化性能,用于多巴胺的檢測。主要內(nèi)容如下:1、基于色氨酸功能化的石墨烯用于檢測抗壞血酸、多巴胺、尿酸基于色氨酸分子和石墨烯納米片層之間的π-π共軛作用,通過簡單超聲的方法合成一種新型的色氨酸功能化的石墨烯納米復(fù)合材料(Trp-GR)。這種材料與純的石墨烯(GR)相比具有良好的水分散性和更高的導(dǎo)電性。掃描電子顯微鏡(SEM),透射電子顯微鏡(TEM)和拉曼光譜用來表征Trp-GR的表面形貌特征�？箟难�(AA)、多巴胺(DA)和尿酸(UA)在Trp-GR表面的電化學(xué)行為通過循環(huán)伏安法(CV)來表征。AA-DA、DA-UA和UA-AA之間的氧化峰電位分離分別約為182 mV、125 mV和307 mV,這使得AA、DA和UA可以同時測定。差示脈沖伏安法(DPV)被用于在AA、DA和UA的混合樣品中檢測AA、DA和UA。在最優(yōu)化條件下,AA、DA和UA的檢測線性范圍分別為0.2~12.9 mM、0.5~110μM、10~1000μM,檢出限分別為5.65μM、0.171μM和0.221μM。此外,該修飾電極被用于實際樣品的檢測。2、金納米/色氨酸功能化的石墨烯用于靈敏檢測多巴胺通過電化學(xué)沉積的方法將金納米直接沉積在色氨酸功能化石墨烯上成功制備了一種簡單且均一的金納米/色氨酸功能化石墨烯(AuNPs/Trp-GR)納米復(fù)合材料。AuNPs/Trp-GR的納米結(jié)構(gòu)通過掃描電子顯微鏡(SEM)和X射線能量分散能譜(EDS)進(jìn)行了表征,證明金納米均勻的分布在Trp-GR上,這可能是由于Trp-GR為金納米的沉積提供了更多的結(jié)合位點。AuNPs/Trp-GR/GCE對多巴胺的電催化活性通過循環(huán)伏安法(CV)和差示脈沖伏安法(DPV)進(jìn)行了系統(tǒng)的研究。在優(yōu)化條件下,對于多巴胺的檢測得到了一個較寬且有意義的線性范圍(0.5~411μM)和一個較低的檢測限(0.056μM),且具有良好的重復(fù)性和穩(wěn)定性。此外,修飾電極還成功的用于對實際樣品的分析。
[Abstract]:Graphene is a monolayer two-dimensional nanomaterials formed by sp~2 hybrid of carbon atoms.Because of its high conductivity, large specific surface area and low preparation cost, it is an ideal electrochemical material.However, graphene is hydrophobic and has poor dispersion in solution. Moreover, the van der Waals force and the strong 蟺-蟺 stacking between graphene layers lead to irreversible condensation and even restack to graphite.These all limit the further application of graphene.Functionalization of graphene to improve the dispersion of graphene in solution is the most important method for the application of graphene materials at present.In this paper, based on the properties of graphene, tryptophan molecules are used to functionalize graphene through 蟺-蟺 interaction to improve its dispersity and electrocatalytic performance.The tryptophan functionalized graphene was modified on the surface of the electrode, and a corresponding sensor was constructed to detect ascorbic acid, dopamine and uric acid separately or simultaneously, and then electrodeposited gold nanoparticles on the tryptophan functionalized graphene.The synergism between them can further improve the electrocatalytic performance and be used for the detection of dopamine.The main contents are as follows: 1. Graphene based on tryptophan functionalization is used to detect ascorbic acid, dopamine, uric acid based on 蟺-蟺 conjugation between tryptophan molecules and graphene nanoliths.A novel tryptophan functionalized graphene nanocomposite was synthesized by simple ultrasonic method.This kind of material has better water dispersibility and higher conductivity than pure graphene grass.Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy were used to characterize the surface morphology of Trp-GR.鎶楀潖琛，

本文編號：1711672