天堂国产午夜亚洲专区-少妇人妻综合久久蜜臀-国产成人户外露出视频在线-国产91传媒一区二区三区

當(dāng)前位置:主頁 > 科技論文 > 化學(xué)論文 >

窄帶隙共軛聚合物的合成及其光電性能研究

發(fā)布時間:2018-05-07 04:03

  本文選題:非對稱聚合物 + 場效應(yīng)晶體管; 參考:《河北大學(xué)》2017年碩士論文


【摘要】:自21世紀(jì)以來,由于化石能源的不斷消耗,能源枯竭、環(huán)境污染等問題日益嚴(yán)峻。尋找一種可代替化石能源的清潔能源勢在必行,于是科學(xué)家將目光投向于清潔的太陽能。從此,太陽能電池成為各領(lǐng)域的研究熱點(diǎn)。有機(jī)太陽能電池因低成本、輕柔、可印刷制備等優(yōu)點(diǎn),具有重要的應(yīng)用前景。有機(jī)共軛材料作為一種新興的功能材料,由于其具有豐富的光、電、磁等功能特性,已在有機(jī)太陽能電池(OSCs)和有機(jī)場效應(yīng)晶體管(FETs)領(lǐng)域得到廣泛的研究。然而提高有機(jī)太陽能電池的光電轉(zhuǎn)換效率,從而提高太陽能的利用率仍是人們努力的方向。通過設(shè)計并合成具有窄帶隙和較低的HOMO能級的有機(jī)共軛材料,優(yōu)化分子結(jié)構(gòu),改善材料的各項(xiàng)性能,是提高太陽能電池效率的主要方法。本論文圍繞新型共軛分子的設(shè)計、合成及其在有機(jī)場效應(yīng)晶體管和有機(jī)太陽能電池中的應(yīng)用展開研究工作,具體內(nèi)容如下:1.成功設(shè)計并合成了一個以噻吩和噻唑作為橋聯(lián)基團(tuán)的非對稱DPP共軛聚合物。對其光電性能的研究發(fā)現(xiàn),不對稱DPP聚合物具有較窄的帶隙,合適的HOMO與LUMO能級(-5.48 eV與-4.03 eV),以及高的空穴遷移率(3.05 cm2 V-1 s-1)。將其作為電子給體應(yīng)用于太陽能電池中,能量轉(zhuǎn)換效率高達(dá)5.9%,顯示出較高的填充因子0.66與短路電流密度12.0 mA cm-2。通過對活性層形貌的研究發(fā)現(xiàn),非對稱聚合物與PC71BM共混的薄膜中表現(xiàn)出大的相分離尺寸,導(dǎo)致其相對低的光電流。以上結(jié)果表明,通過將不同芳香基團(tuán)連接在聚合物主鏈?zhǔn)钦{(diào)節(jié)能級,實(shí)現(xiàn)高性能有機(jī)光伏器件的一種有效方法。2.通過在傒酰亞胺分子(SdiPBI)中引入兩個氰基基團(tuán),成功設(shè)計并合成了一種具有低LUMO能級(-4.56 eV)的小分子受體材料(SdiCNPBI)。對其光電性能研究發(fā)現(xiàn),SdiCNPBI分子在溶液和薄膜中具有相似的吸收光譜。由于強(qiáng)吸電子基團(tuán)氰基的作用,SdiCNPBI的HOMO和LUMO能級顯著降低,分別為-6.59 eV和-4.56 eV。將該分子作為電子受體應(yīng)用于非富勒烯太陽能電池中,與不含氰基的電子受體對比,成功實(shí)現(xiàn)能量轉(zhuǎn)換效率從0.1%提高到1.4%。采用光致發(fā)光技術(shù)(PL)進(jìn)一步證實(shí)了有效的電荷分離。以上結(jié)果證明,扭曲的雙PBI單元有效阻止共混薄膜中分子的聚集,缺電子基團(tuán)的引入降低分子能級從而提高電荷分離驅(qū)動力,最終實(shí)現(xiàn)了給體材料的LUMO能級低于-4.0 eV下優(yōu)異的光電性能。
[Abstract]:Since the 21st century, due to the constant consumption of fossil energy, energy depletion, environmental pollution and other increasingly serious problems. It is imperative to find a clean alternative to fossil energy, so scientists look to clean solar energy. Since then, solar cells have become a research hotspot in various fields. Organic solar cells have important applications due to their advantages of low cost, softness, printability and so on. As a new functional material, organic conjugated materials have been widely studied in the field of organic solar cells (OSCs) and airfield effect transistors (FETs) because of their rich optical, electrical and magnetic properties. However, improving the photovoltaic conversion efficiency of organic solar cells and thus improving the utilization rate of solar energy is still the direction of people's efforts. By designing and synthesizing organic conjugated materials with narrow band gap and lower HOMO energy level, optimizing the molecular structure and improving the properties of the materials are the main methods to improve the efficiency of solar cells. This thesis focuses on the design, synthesis and application of novel conjugated molecules in organic solar cells and airfield effect transistors. The main contents are as follows: 1. An asymmetric DPP conjugated polymer with thiophene and thiazole as bridging group was successfully designed and synthesized. It is found that asymmetric DPP polymers have narrow band gap, suitable HOMO and LUMO energy levels of -5.48 EV and -4.03 EV, and high hole mobility of 3.05 cm2 V-1 s-1C. When it is used as an electron donor in solar cells, the energy conversion efficiency is as high as 5.9, showing a high filling factor of 0.66 and a short-circuit current density of 12.0 Ma cm-2. By studying the morphology of the active layer, it is found that the large phase separation size in the films mixed with asymmetric polymer and PC71BM leads to a relatively low photocurrent. The results show that connecting different aromatic groups to the main chain of the polymer is an effective way to achieve high performance organic photovoltaic devices by regulating the energy levels. By introducing two cyanide groups into SdiPBI, a small molecule receptor material with low LUMO level (-4.56 EV) was successfully designed and synthesized. It is found that SdiCNPBI molecules have similar absorption spectra in solution and thin films. The HOMO and LUMO energy levels of SdiCNPBI were significantly decreased to -6.59eV and -4.56eV, respectively. The molecule was used as an electron receptor in non-fullerene solar cells, and compared with the electron receptors without cyanide group, the energy conversion efficiency was improved from 0.1% to 1.4%. The effective charge separation was further confirmed by photoluminescence (PL) technique. The above results show that the twisted double PBI element effectively prevents the molecular aggregation in the blend film, and the introduction of the electron deficient group reduces the molecular energy level, thus increasing the charge separation driving force. Finally, the LUMO energy level of the donor is lower than -4.0 EV.
【學(xué)位授予單位】:河北大學(xué)
【學(xué)位級別】:碩士
【學(xué)位授予年份】:2017
【分類號】:O633.5

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 劉欣;蘇仕健;曹鏞;;基于聚合物給體與非富勒烯有機(jī)小分子受體材料的有機(jī)太陽能電池研究進(jìn)展[J];高分子通報;2014年12期

,

本文編號:1855306

資料下載
論文發(fā)表

本文鏈接:http://sikaile.net/kejilunwen/huaxue/1855306.html


Copyright(c)文論論文網(wǎng)All Rights Reserved | 網(wǎng)站地圖 |

版權(quán)申明:資料由用戶7c9e2***提供,本站僅收錄摘要或目錄,作者需要刪除請E-mail郵箱bigeng88@qq.com