【作者】 杨勇；

【导师】 牛和林；

【作者基本信息】 安徽大学 ， 化学工程（专业学位）， 2021， 硕士

【摘要】 金属有机凝胶（MOGs）作为新型的一种多功能软材料,具有比表面积大,响应外界刺激,温和简单的合成条件,热稳定性好和荧光特性良好等优点,使其在催化,吸附/分离,电化学传感,超电以及检测等诸多方面具有广泛的应用。随着人们对环境污染和健康问题的日益关注,因此检测开发新型的荧光传感材料用于检测环境中的污染物显得尤为重要。具有优异荧光特性的发光金属有机凝胶（LMOGs）得益于上述各种优点可以带来出色的选择性,灵敏度和可回收性,可以用来构建优异的荧光传感器用于检测环境中的各种污染物。本论文采用水热-溶剂热法或加热辅助超声法制备一系列具有稳定荧光性能的LMOGs材料,利用仪器平台各种表征仪器表征了所得LMOGs材料的组成结构,凝胶性质及形貌特征,利用紫外吸收分光光度计,荧光分光光度计和荧光寿命的测量来分析和研究了所得LMOGs材料的荧光性能以及构建荧光传感器用于检测各种环境中的目标污染物和探索相应的检测机制。主要研究内容如下:1.铕掺杂锆基金属有机凝胶（Zr/Eu-MOG）作为荧光传感器用于检测水中的头孢曲松钠和铁氰酸根离子抗生素通常被用来预防和治疗由于细菌传播而导致的疾病。然而,抗生素的广泛应用已经导致了这种药物在环境水体中的长时间存在。它是一种对环境和人体身心健康造成很多严重危害的持久性污染物。同样,重金属离子也是水相环境中常见的污染物之一。因此需要研究和开发一种用于简便快速检测水中抗生素和重金属离子的材料和方法。以无水氯化锆（Zr Cl₄）为金属源,均苯三甲酸（BTC）为配体,六水硝酸铕[Eu（NO₃）₃·6H₂O]为掺杂镧系金属源,通过一步水热-溶剂热法制备了具有优异发光性能的Zr/Eu-MOG构建荧光传感器用于水中抗生素和离子的选择性检测。荧光实验表明,Zr/Eu-MOG干凝胶可以特异性地识别水中的头孢曲松钠（CRO）和铁氰酸根离子([Fe（CN）₆]^3-)。计算得出的CRO和[Fe（CN）₆]^3-的检测限分别低至27.2 ppb和40.8 ppb。另外在其它抗生素或离子存在的条件下不会影响Zr/Eu-MOG干凝胶对CRO和[Fe（CN）₆]^3-的快速检测,说明Zr/Eu-MOG干凝胶对检测CRO和[Fe（CN）₆]^3-具有良好的特异性,高效性和灵敏性。相信这种镧系掺杂策略将为MOGs材料的合成方法和功能应用开辟新的机遇。2.组氨酸触发的配位诱导发射锆基金属有机凝胶（Zr-MOG-His）传感平台用于特异性识别呋喃妥因抗生素类药物在对一些疾病的临床医学上的治疗具有非常重要的贡献和意义。但是,滥用或混入环境水质中对人类健康安全具有非常严重的负面影响。确定抗生素的方法有很多,包括质谱法,电化学,比色分析和吸收光谱法等等。然而,这些方法中的大多数具有高成本,长且复杂的合成和设计时间,并且需要专业的技术人员。因此,研究人员渴望找到易于合成,条件温和,功能强大且易于操作的材料,用于测定抗生素。因此,在这里,使用BTC充当第一配体,而L-组氨酸（His）充当第二配体通过典型的水热溶剂热法合成制备了氨基酸配位诱导发射的锆基金属有机凝胶（Zr-MOG-His）,以解决或缓解上述问题。相应的荧光实验结果表明,Zr-MOG-His对水中的呋喃妥因（FAN）具有优异的淬灭效应,且淬灭效率高达91.59%。即使在其他抗生素的干扰下,淬灭作用在不到10 s内达到平衡,并且检测限低至31.4 ppb,以上结果表明Zr-MOG-His可作为荧光传感器用于快速高效选择性检测痕量FAN。3.镧系双金属有机凝胶（Eu/Tb-G）作为自校准荧光传感器用于检测甲醇在本工作中,使用常见的低分子量胶凝剂BTC和镧系金属离子(Tb³⁺和Eu³⁺)制备了一系列优异的发光超分子金属有机凝胶,其表现出镧系元素的特征性发光。其中通过共掺杂策略制备了具有黄光发射信号的双金属有机凝胶（Eu/Tb-G）,其共同展示出Eu³⁺和Tb³⁺的特征荧光发射。发现甲醇可以在不影响Eu³⁺的特征发射的情况下增加了Tb³⁺的荧光强度。以Eu³⁺的稳定发射作为内部参考,并以变化的Tb³⁺的变化发射作为目标检测信号,获得了内部自校准的荧光传感器用于检测甲醇。并且这种荧光变化（发光颜色从黄色转变成绿色）可以通过肉眼直接观察。荧光寿命的测量证实了这种变化归因于传感器中的能量转移过程的阻断。另外,所制备的Eu/Tb-G纸基传感器对甲醇蒸汽具有良好的刺激响应和可重复性。以上结果可以将Eu/Tb-G建立为用于检测甲醇及其蒸汽的比率和比色荧光传感器。更多还原

【Abstract】 Metal organic gels（MOGs）is a newly developed functional soft material in recent years.It has the merits of large specific surface area,response to external stimuli,mild and simple synthesis conditions,thermal stability and excellent fluorescence characteristics,which has an extensive range of applications in many fields such as catalysis,adsorption/separation,electrochemical sensing,super-electricity and detection.As people pay more attentions to environmental pollution and health problems,it is particularly important to detect and develop new types of fluorescent sensing materials for detecting pollutants in the environment.Luminescent metal organic gels（LMOGs）with excellent fluorescence characteristics can bring excellent selectivity,sensitivity and recyclability due to the above-mentioned various advantages,and can be used to construct excellent fluorescence sensors for detecting various types of environment pollutants.In this paper,a series of LMOGs materials with stable fluorescence properties are prepared by hydrothermal-solvothermal method or heating-assisted ultrasonic method.Various characterization instruments of the instrument platform are used to characterize the composition structure,gel properties and morphological characteristics of the obtained LMOGs.Ultraviolet absorption spectrophotometer,fluorescence spectrophotometer and fluorescence lifetime measurement are used to analyze and study the fluorescence properties of the obtained LMOGs materials and construct fluorescence sensors to detect target pollutants in various environments and explore the corresponding detection mechanisms.The main contents as follows:1.Europium-doped zirconium-based metal organic gel（Zr/Eu-MOG）is used as a fluorescence sensor to detect ceftriaxone sodium and ferricyanides ion in waterAntibiotics are usually used to prevent and treat diseases caused by the spread of bacteria.However,the widespread use of antibiotics has led to the long-term existence of this drug in environmental water.It is a persistent pollutant that causes serious harm to the environment and humans.Similarly,heavy metal ions are also one of the common pollutants in wastewater.Therefore,it is required to exploit a material and method for detection of antibiotics and heavy metal ions in water.In this work,anhydrous zirconium chloride（Zr Cl₄）as the metal source,1,3,5-benzenetricarboxylic acid（BTC）as the ligand,and europium nitrate hexahydrate（Eu（NO3）₃·6H₂O）as the doping metal source.Zr/Eu-MOG with excellent luminescence properties was prepared by one-step hydrothermal-solvothermal method to construct a fluorescent sensor for the alternative recognition of antibiotics and ions in wastewater.Fluorescence experiments show that Zr/Eu-MOG xerogel can specifically recognize ceftriaxone sodium（CRO）and ferric acid ion([Fe（CN）₆]^3-)in water.The calculated detection limits of CRO and[Fe（CN）₆]^3-are as low as 27.2 ppb and 40.8 ppb,respectively.In addition,the presence of other antibiotics or ions will not affect the rapid detection of CRO and[Fe（CN）₆]^3-by Zr/Eu-MOG xerogel,indicating that Zr/Eu-MOG xerogel is useful for detecting CRO and[Fe（CN）₆]^3-has good specificity,high efficiency and sensitivity.It is believed that this lanthanide doping strategy will open up new opportunities for the synthesis methods and functional applications of MOGs materials.2.Histidine-triggered coordination induced emission zirconium-based metal organic gel（Zr-MOG-His）sensor platform for specific recognition of nitrofurantoinAntibiotic drugs play a very important role in the treatment of some diseases in clinical medicine.However,the abuse or mixing of food has a very serious negative impact on human health and safety.There are many ways to determine antibiotics,including mass spectrometry,electrochemical analysis,atomic absorption spectroscopy and colorimetric analysis.However,most of these methods have high cost,long and complicated synthesis time and design time,and require professional technicians.Therefore,researchers are eager to find materials that are easy to synthesize,have mild conditions,are powerful,and are easy to manipulate for the determination of antibiotics.Therefore,in this work,BTC as the first ligand and L-histidine（His）as the second ligand.A zirconium-based metal organic gel（Zr-MOG-His）to solve or alleviate the above problems.The corresponding fluorescence experiment results show that Zr-MOG-His has excellent quenching effect on nitrofurantoin（FAN）in water,and the quenching efficiency is as high as 91.59%.Even under the interference of other antibiotics,the quenching effect reaches equilibrium in less than 10s,and the detection limit is as low as 31.4 ppb.The above results indicate that Zr-MOG-His can be used as a fluorescence sensor for rapid,efficient and selective detection of trace FAN.3.Lanthanide bimetallic organic gel（Eu/Tb-G）as a self-calibrated fluorescence sensor for methanol detectionIn this work,the common low molecular weight gelling agents BTC and lanthanide metal ions(Tb³⁺and Eu³⁺)have been used to prepare a series of excellent luminescent supramolecular metal organic gels,which exhibit the characteristic luminescence of lanthanides.Among them,the bimetallic organic gel（Eu/Tb-G）with yellow light emission signal was prepared by co-doping strategy,and exhibited the characteristic fluorescence emission of both Eu³⁺and Tb³⁺.Methanol can increase the fluorescence intensity of Tb³⁺without affecting the characteristic emission of Eu³⁺.Taking the stable emission of Eu³⁺as the internal reference,and the changing emission of the changing Tb³⁺as the target detection signal,an internal self-calibrated fluorescence sensor was obtained for the detection of methanol.And this change in fluorescence（the color of light from yellow to green）can be straightly watched by the naked eye.The fluorescence lifetime measurement confirmed that this change is due to the interruption of the energy transfer process in the sensor.In addition,the prepared Eu/Tb-G paper-based sensor has good stimulus response and repeatability to methanol vapor.The above results can establish Eu/Tb-G as a ratio and colorimetric fluorescence sensor for detecting methanol and its vapor.更多还原