本文關(guān)鍵詞： 碳量子點(diǎn)(CQDs) 硝酸氧化 微波法 滲析 熒光量子產(chǎn)率(QY)　出處：《中國地質(zhì)大學(xué)(北京)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：迄今為止應(yīng)用最廣的是金屬半導(dǎo)體量子點(diǎn),且廣泛應(yīng)用于電子器件和量子計算等領(lǐng)域,而該量子點(diǎn)存在的最大弊端是有較大的毒性,制備成本較高,因此科學(xué)家們嘗試尋找一種可以取代的新型量子點(diǎn)即碳量子點(diǎn)。碳量子點(diǎn)的直徑在20nm左右。而碳量子點(diǎn)最大的優(yōu)點(diǎn)在于低毒性、良好的生物相容性,較強(qiáng)的發(fā)光性、以及光穩(wěn)定性,可廣泛應(yīng)用于生物傳感器及生物分子的檢測、細(xì)胞成像等。在此基礎(chǔ)上,為了制備碳量子點(diǎn)開始尋找豐富的原料,煤炭是我國的主要能源,依據(jù)結(jié)構(gòu)和組成不同,煤炭分為無煙煤、煙煤、褐煤三大類,其中煙煤分為低變質(zhì)煙煤、中變質(zhì)煙煤,其中低變質(zhì)煙煤和褐煤一起統(tǒng)稱為低階煤。因為目前為止對于低階煤結(jié)構(gòu)的認(rèn)知還沒有準(zhǔn)確的結(jié)論,而且其種類繁多導(dǎo)致結(jié)構(gòu)也會相應(yīng)不同,因此低階煤的研究以及應(yīng)用是目前一個很重要的課題。論文通過硝酸氧化法和微波消解法制備碳量子點(diǎn),研究了不同產(chǎn)地的低階煤制備碳量子點(diǎn)的工藝,優(yōu)化溫度、時間、酸濃度、提純等實驗條件,發(fā)現(xiàn)龍口脫灰煤效果較好,反應(yīng)溫度為130℃,反應(yīng)時間為12h。通過紅外(FTIR)、碳核磁共振(13CNMR)、X射線衍射(XRD)、光電子能譜(XPS)、透射電鏡(TEM)、原子力顯微鏡(AFM)、拉曼光譜(Raman)、熒光光譜(PL)等,表征了碳量子點(diǎn)的結(jié)構(gòu)(粒徑、官能團(tuán)等)和性質(zhì)。并表征了碳量子點(diǎn)在激光下激發(fā)下的熒光。提出煤與硝酸反應(yīng)生成CQDs的機(jī)理:除了煤大分子的硝化的過程,同時還伴隨Scholl反應(yīng)導(dǎo)致的芳香簇稠并過程。分別用聚乙二醇(PEG)、超酸(雙(三氟甲烷)磺酰亞胺TFSI)改性碳量子點(diǎn),發(fā)現(xiàn)改性后熒光量子產(chǎn)率提高。利用碳量子點(diǎn)制備出有熒光性質(zhì)的靜電紡絲PVA膜和熒光墨水,得到了較好的效果。
[Abstract]:So far the most widely used metal semiconductor quantum dots, and widely used in electronic devices, quantum computing and other fields, and the biggest disadvantage of this quantum dot is that it has greater toxicity and high cost of preparation. So scientists try to find a new quantum dot which can be replaced by carbon quantum dot. The diameter of carbon quantum dot is about 20nm. The biggest advantage of carbon quantum dot is its low toxicity and good biocompatibility. Because of its strong luminescence and photostability, it can be widely used in biosensors and biomolecules detection, cell imaging and so on. On this basis, we began to search for rich raw materials for the preparation of carbon quantum dots. Coal is the main energy in China. According to the structure and composition, coal is divided into anthracite, bituminous coal and lignite, among which bituminous coal is divided into low metamorphic bituminous coal and medium metamorphic bituminous coal. Low metamorphic bituminous coal and lignite are referred to as low rank coal together, because there is no accurate conclusion about the structure of low rank coal so far, and many kinds of bituminous coal lead to different structures. Therefore, the research and application of low-rank coal is a very important subject at present. In this paper, carbon quantum dots are prepared by nitric acid oxidation and microwave digestion, and the process of preparing carbon quantum dots from low-rank coal from different habitats is studied. Optimizing the experimental conditions such as temperature, time, acid concentration, purification and so on, it was found that Longkou desliming coal had better effect, reaction temperature was 130 鈩，

本文編號：1466830