本文選題：多價(jià)主客結(jié)合 + 金納米粒子　； 參考：《北京化工大學(xué)》2017年碩士論文

【摘要】：金納米粒子(AuNPs)由于具有其優(yōu)異的催化性能、與粒子尺寸相關(guān)的光學(xué)性能、良好的生物相容性以及較高的消光系數(shù)等而被廣泛的研究,特別是其催化性能的應(yīng)用已涉及化學(xué)工業(yè)領(lǐng)域。但是作為貴金屬,其重復(fù)應(yīng)用也是頗受關(guān)注的,因此近幾年所提出的重復(fù)應(yīng)用方法也越來(lái)越多,但多是在溶液中轉(zhuǎn)移或者循環(huán)分散與團(tuán)聚等,并不是真正意義上的回收。所以目前也有很多科學(xué)家集中在AuNPs的回收方面,方法多種多樣,包括磁性回收、離心分離等,無(wú)論是哪種方法,都需要與其它物質(zhì)結(jié)合,而且結(jié)合后的復(fù)合體在應(yīng)用時(shí)以及回收后都不可分離,重復(fù)利用前都需要經(jīng)過(guò)清洗和干燥過(guò)程,這種批處理模式耗時(shí)耗力耗資。為滿足工業(yè)中高效、節(jié)約的需求,值得一提的是將AuNPs固定到多孔基材上或者是絲狀物質(zhì)上,這樣可以通過(guò)過(guò)濾的方式實(shí)現(xiàn)持續(xù)催化的效果,但是其不可修復(fù)性限制了其應(yīng)用�；谝陨蠁栴},本實(shí)驗(yàn)借助β-環(huán)糊精(β-CD)和偶氮苯(Azo)多價(jià)主客結(jié)合作用的高強(qiáng)度以及其光響應(yīng)性,制備了 AuNPs功能化的催化基板。前人實(shí)驗(yàn)中所固定的AuNPs與基材不可分離,這樣會(huì)在一定程度上限制AuNPs功能的發(fā)揮。所以在實(shí)驗(yàn)的第一部分,一方面制備了直徑為17.27 nm的AuNPs,通過(guò)S-Au鍵在其表面包覆一層Azo分子。另一方面,通過(guò)層層功能化將改性的β-CD結(jié)合到鎳泡沫(PNi)基板上,再在多價(jià)主客結(jié)合力的作用下將Azo包覆的AuNPs固定在β-CD功能化的PNi上,在紫外燈的照射下Azo與β-CD的主客結(jié)合失效,AuNPs被釋放下來(lái),相反,當(dāng)用可見光照射時(shí),AuNPs可被重新固定到PNi上,實(shí)現(xiàn)了 AuNPs的按需釋放和回收。由于Azo分子的異構(gòu)化存在空間位阻效應(yīng),因此其在AuNPs表面的結(jié)合數(shù)量有限,無(wú)法通過(guò)多價(jià)主客結(jié)合作用將17.27 nm的AuNPs大量的固定于表面,影響AuNPs功能化表面的應(yīng)用,所以第二部分實(shí)驗(yàn)制備了表面含β-CD的AuNPs,其平均粒徑僅僅3.27 nm,同樣利用多價(jià)主客結(jié)合作用將其固定在Azo功能化的PNi表面,所得基底可直接用做4-硝基苯酚還原過(guò)程的催化劑,催化效率高于95%,另外,當(dāng)把剪碎的基底填塞到針管中可制得催化效率接近95%的“催化床”。一旦表面的AuNPs失效,根據(jù)第一部分實(shí)驗(yàn)中的按需釋放機(jī)理,還可實(shí)現(xiàn)“催化床”的原位修復(fù),極大的符合了工業(yè)需求。
[Abstract]:Gold nanoparticles (AuNPs) have been widely studied because of their excellent catalytic properties, optical properties related to particle size, good biocompatibility and high extinction coefficient. In particular, the application of its catalytic performance has been related to the chemical industry. However, as precious metals, its repeated application is also very concerned, so in recent years, more and more repeated application methods have been put forward, but most of them are transferred in solution, dispersed in circulation and agglomerated, and are not really recycled. So at present, there are many scientists who concentrate on the recovery of AuNPs. There are a variety of methods, including magnetic recovery, centrifugal separation, and so on. Either way, it needs to be combined with other substances. The combined complex can not be separated when it is used or recovered. It needs cleaning and drying process before reuse. This batch treatment model is time-consuming and costly. In order to meet the needs of high efficiency and economy in industry, it is worth mentioning that AuNPs are immobilized on porous substrates or filamentous materials, which can achieve the effect of continuous catalysis by filtration, but its application is limited by irreparability. Based on the above problems, AuNPs functional catalytic substrate was prepared by using the high intensity of 尾 -cyclodextrin (尾 -CD) binding with azobenzene (Azo) multivalent host and guest interaction and its photoresponsiveness. The fixed AuNPs in previous experiments can not be separated from the substrate, which limits the function of AuNPs to some extent. In the first part of the experiment, on the one hand, the AuNPs with a diameter of 17.27 nm were prepared, and a layer of Azo molecules was coated on the surface by S-Au bond. On the other hand, the modified 尾 -CD was bonded to the nickel foam (PNi) substrate by layer functionalization, and then the Azo coated AuNPs were immobilized on the 尾 -CD functionalized PNi under the action of multivalent host and guest binding force. ANPs of Azo and 尾 -CD were released under UV irradiation. On the contrary, when irradiated with visible light, ANPs could be reimmobilized to PNi, thus realizing the on-demand release and recovery of AuNPs. Because the isomerization of Azo molecule has steric resistance effect, its binding quantity on the surface of AuNPs is limited, so it is unable to immobilize a large amount of 17.27nm AuNPs on the surface through multivalent host and guest binding, which affects the application of the functionalized surface of AuNPs. In the second part, AuNPs with 尾 -CD on the surface were prepared. The average particle size of AuNPs was only 3.27 nm. It was also immobilized on the surface of Azo functionalized PNi by multivalent host and guest binding. The obtained substrate could be directly used as catalyst for the reduction of 4-nitrophenol. The catalytic efficiency is higher than 95%, in addition, when the shredded substrate is filled in the needle tube, the catalytic efficiency can be nearly 95% of the "catalytic bed". Once the surface AuNPs fail, according to the mechanism of on-demand release in the first part of the experiment, the in-situ repair of "catalytic bed" can be realized, which greatly meets the industrial demand.
【學(xué)位授予單位】：北京化工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：O643.36

【相似文獻(xiàn)】

相關(guān)博士學(xué)位論文 前2條

1 劉玉玲;基于二價(jià)金屬—鈷氰根的主客體型框架化合物的相變和介電性質(zhì)研究[D];東南大學(xué);2017年

2 宋濤;基于主客體系金屬—有機(jī)框架材料的光譜調(diào)控及其白光發(fā)射性能研究[D];浙江大學(xué);2017年

相關(guān)碩士學(xué)位論文 前1條

1 周大緩;多價(jià)主客結(jié)合方法構(gòu)建可修復(fù)的催化基板[D];北京化工大學(xué);2017年

，

本文編號(hào)：2102882