本文選題：共軛高分子　切入點：拉直碳納米管　出處：《浙江大學(xué)》2017年博士論文　論文類型：學(xué)位論文

【摘要】：共軛高分子由于其剛性分子鏈結(jié)構(gòu)和較強的分子間相互作用,因而具有較好的結(jié)晶性和優(yōu)異的光電性能,被廣泛應(yīng)用于光電領(lǐng)域中。本文以聚(3-己基噻吩)(P3HT)及含P3HT的嵌段共聚物為研究對象,研究共軛高分子與同樣具有共軛結(jié)構(gòu)的碳納米管(CNTs)之間的相互作用、共軛高分子有序自組裝的性質(zhì)和作為有機給體材料在水相制備太陽能電池的應(yīng)用。伸直的CNTs對含CNTs的材料和器件性能的提升都具有重要的意義。本論文首先發(fā)現(xiàn),P3HT可在單壁碳納米管(SWCNTs)表面外延結(jié)晶形成晶須,在合適的條件下能顯著地拉直SWCNTs。改變P3HT溶液結(jié)晶條件,發(fā)現(xiàn)低濃度的SWCNTs和較高的SWCNT/P3HT質(zhì)量比有利于彎曲的SWCNTs被拉直。實驗發(fā)現(xiàn),在溶液中P3HT分子鏈就可附著在SWCNTs管壁表面,從而對SWCNTs產(chǎn)生拉直作用,而非由外延結(jié)晶形成的P3HT納米纖維晶體驅(qū)動SWCNTs拉直。用X-射線光電子能譜、紫外吸收光譜和光致發(fā)光光譜光譜進(jìn)一步揭示了復(fù)合物的內(nèi)在作用機理,發(fā)現(xiàn)P3HT分子鏈和SWCNTs之間存在強的π-π相互作用,使SWCNTs的持續(xù)長度得到顯著增強。P3HT對SWCNTs的拉直效應(yīng)較弱,會被SWCNTs之間的纏繞和橋連導(dǎo)致的局部應(yīng)力抵消,這在高濃度的SWCNTs和低的SWCNT/P3HT質(zhì)量比條件下能觀察到,P3HT也難以拉直彎曲模量較大的MWCNTs�？刂乒曹椌酆衔飶奈⒂^尺度到宏觀尺度的形貌是一個很關(guān)鍵的技術(shù)挑戰(zhàn),聚合物的聚集態(tài)形貌影響著相應(yīng)器件的性能,進(jìn)而影響共軛聚合物在電子設(shè)備上的應(yīng)用推廣。本論文考慮到P3HT分子鏈較強的結(jié)晶性,將P3HT溶液滴涂在基底上,受三相界面處溶劑揮發(fā)影響,結(jié)晶形成纖維。通過調(diào)控外界的結(jié)晶條件,促使P3HT分子鏈有序堆積形成纖維,并通過傾斜基底提供外界應(yīng)力,誘導(dǎo)P3HT纖維有序取向,形成高度取向的纖維陣列薄膜。通過掠入射小角X-射線散射和偏振紫外可見光吸收光譜,發(fā)現(xiàn)P3HT分子鏈在纖維陣列中的排列結(jié)構(gòu)主要是“側(cè)立”結(jié)構(gòu),主鏈方向與納米纖維垂直。取向的納米纖維陣列,作為導(dǎo)電網(wǎng)絡(luò)應(yīng)用于有機場效應(yīng)晶體管,能顯著地提升載流子遷移率。聚合物分子鏈的有序堆積,纖維緊密排列和高度取向,都有利于提高薄膜的載流子遷移率。本工作制備取向P3HT纖維薄膜的方法簡單高效,對共軛聚合物在電子器件中的應(yīng)用有極其重要的意義。含P3HT的雙親性嵌段共聚物能在選擇性溶劑水中可進(jìn)行自組裝,形成有序的納米膠束結(jié)構(gòu)。同時由于P3HT是半導(dǎo)體高分子,因此含P3HT的雙親性嵌段共聚物可望應(yīng)用于水相制備太陽能電池。本論文合成了聚(3-已基噻吩)-b-聚丙烯酸(P3HT-b-PAA)雙親性嵌段共聚物,并研究其在水溶液中自組裝成膠束的形貌,發(fā)現(xiàn)通過加入P3HT均聚物,膠束由球狀或棒狀轉(zhuǎn)化為纖維狀。將膠束與水溶性的CdTe納米晶復(fù)合,應(yīng)用到太陽能電池中,發(fā)現(xiàn)P3HT-b-PAA雙親性嵌段共聚物的引入能顯著改善復(fù)合物的光電性能與薄膜的形貌。本論文通過嵌段共聚物膠束和水溶性納米晶水相制備雜化太陽能電池,最高效率能達(dá)到4.8%,為潔凈和低成本制備高效太陽能電池提供了一種思路。
[Abstract]:Conjugated polymer interactions due to the rigid molecular chain structure and strong intermolecular, so it has good crystallinity and excellent optical properties, is widely used in photoelectric field. Based on poly (hexylthiophene 3-) (P3HT) and P3HT containing block copolymer as the object of the study of the conjugated polymer with the same the conjugate structure of carbon nanotubes (CNTs) interaction between the conjugated polymer ordered properties of self assembly and application as organic donor materials in aqueous preparation of solar cells. The extension of CNTs is of great significance to material containing CNTs and device performance promotion. This paper first found in P3HT single walled carbon nanotubes (SWCNTs) surface of epitaxial crystal whisker formation, can significantly change the crystallization conditions straightened SWCNTs. P3HT solution under suitable conditions, we found that low concentrations of SWCNTs and higher SWCNT/ P3HT than the good quality In the bending of SWCNTs be straightened. The experimental results showed that, in the solution of P3HT molecular chain can be attached on the surface of the SWCNTs tube wall, resulting in straightening effect on SWCNTs, rather than by the epitaxial crystallization of P3HT nano fiber crystal formation SWCNTs straight. Driven by X- ray photoelectron spectroscopy, UV absorption spectroscopy and photoluminescence spectroscopy spectroscopy further reveals the intrinsic mechanism of the complexes, found strong pi pi interactions between the molecular chains of P3HT and SWCNTs, the length of SWCNTs can be significantly enhanced to straighten out the effect of.P3HT on SWCNTs is weak, SWCNTs will be between the winding and bridge caused by local stress offset, the observed in high the concentration of SWCNTs and low SWCNT/P3HT ratio to P3HT, it is difficult to straighten the flexural modulus of the larger MWCNTs. control of conjugated polymers from micro scale to macro scale morphology is a key technical challenge, Morphology of the polymer affects the properties of corresponding devices, thereby affecting the popularization and application of conjugated polymers in electronic devices. In this dissertation, considering the crystallization of P3HT molecular chain is strong, the P3HT solution is coated on the substrate, the three-phase interface effect of solvent evaporation, crystallization to form fibers. Through crystallization conditions control outside. The P3HT chain ordered to form fibers and provide external stress by tilting the substrate induced ordered orientation of P3HT fiber, fiber array film to form a highly oriented. By grazing incidence small angle X- ray scattering and polarized UV visible light absorption spectrum, P3HT molecular chain structure in the fiber array is the main side "stand structure, main direction and nano fiber. The vertical orientation of the nano fiber array, as a conductive network used in organic field-effect transistors, can significantly enhance carrier mobility. The polymer chains ordered, fibers were closely packed and highly oriented, it is beneficial to improve film carrier mobility. The orientation of the P3HT thin films by the fiber working system is simple and efficient, has important significance for the application of conjugated polymers in electronic devices. The amphiphilic block copolymers in selective solvent can be water the self-assembled into nano micelles containing P3HT, ordered structure. At the same time, because P3HT is a semiconductor polymer, the amphiphilic block copolymers containing P3HT can be used in aqueous preparation of solar cells. This paper synthesized poly (3- thiophene) -b- polyacrylic acid (P3HT-b-PAA) amphiphilic block copolymers, and study the in aqueous solution self assemble into micelle morphology, found by the addition of P3HT homopolymer, micelles transformed from spherical or rod like fibers. The micelle and water-soluble CdTe nanocrystal composite application. The solar cell, found that P3HT-b-PAA amphiphilic block copolymers are introduced and the photoelectric properties of films can significantly improve the complex morphology. The block copolymer micelle and water preparation of hybrid solar cell soluble nanocrystals in aqueous system, the highest efficiency can reach 4.8%, which provides a new way for clean and low cost system preparation of highly efficient solar cells.

【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2017
【分類號】：O633.5
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本文編號：1578804