本文選題：超級(jí)電容器　切入點(diǎn)：碳納米管　出處：《電子科技大學(xué)》2014年碩士論文

【摘要】：超級(jí)電容器是一種新型的儲(chǔ)能裝置,已經(jīng)成功的應(yīng)用于軍事、航天航空、電動(dòng)汽車(chē)、電子通信、交通運(yùn)輸?shù)阮I(lǐng)域。相比于蓄電池,它擁有更大的功率特性和更久的充放電循環(huán)次數(shù),也具有比常規(guī)電容器更高的能量密度。本文對(duì)碳納米管的制備和酸化回流處理進(jìn)行細(xì)致的分析,選用二氧化錳和碳納米管作為超級(jí)電容器的電極材料進(jìn)行了研究,使用場(chǎng)發(fā)射掃描電鏡和X-射線粉末衍射對(duì)材料進(jìn)行了形貌和物相分析,通過(guò)循環(huán)伏安法和恒流充放電測(cè)試研究了電極材料的電化學(xué)性能。主要內(nèi)容如下:1.利用混酸(鹽酸于硝酸比例為3:1)對(duì)碳納米管進(jìn)行了酸化回流處理,通過(guò)觀察其表征可以看出在混酸的強(qiáng)氧化性作用下,碳納米管得到了一定程度的純化,管束被切斷和打開(kāi),提高了碳納米管內(nèi)外表面積的利用率,在90℃下酸化回流4h得到的比電容為17.57F/g,相比于未經(jīng)處理的碳納米管的比電容10.74F/g有較大程度的提高。2.運(yùn)用水熱法制備了不同晶型的二氧化錳納米棒,并在不同反應(yīng)時(shí)間和不同反應(yīng)溫度下進(jìn)行了對(duì)比實(shí)驗(yàn),結(jié)果顯示以氯酸鉀為氧化劑,硫酸錳為錳源,在150℃下反應(yīng)16h得到的α型MnO2有得到了較好的晶化,其長(zhǎng)度大約為為1um左右,直徑為150nm,比電容為111.32F/g,有較好的循環(huán)使用特性;反應(yīng)物為過(guò)硫酸銨和硫酸錳時(shí),發(fā)現(xiàn)在160℃下反應(yīng)15h得到的β型MnO2的長(zhǎng)度為1.3um,直徑為80-150nm,比電容為88.97F/g。3.對(duì)比不同制備方法比較了MnO2/CNT復(fù)合電極材料的電化學(xué)性能。通過(guò)微波等離子化學(xué)氣相沉積在硅片上生長(zhǎng)了碳納米管薄膜,并在此基體上沉積了MnO2,在恒流充放電測(cè)試下復(fù)合電極的比電容為141.31F/g。使用液相共沉淀法制備了MnO2包覆碳納米管結(jié)構(gòu)的電極材料,測(cè)得其比電容為151.76F/g。采用水熱法制備了酸化處理的碳納米管和MnO2納米棒的復(fù)合材料,觀察形貌看出材料中含有明顯的MnO2/CNTs復(fù)合共聚物結(jié)構(gòu),分析恒流充放電曲線得出復(fù)合材料比電容為158.43F/g,相比于未參雜CNTs的MnO2材料有明顯的提高。
[Abstract]:Supercapacitor is a new type of energy storage device, which has been successfully used in military, aerospace, electric vehicles, electronic communications, transportation and other fields.Compared with batteries, it has higher power characteristics, longer charge and discharge cycles and higher energy density than conventional capacitors.In this paper, the preparation of carbon nanotubes and acidizing reflux treatment are analyzed in detail. Manganese dioxide and carbon nanotubes are selected as electrode materials for supercapacitors.Field emission scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) were used to analyze the morphology and phase of the electrode. The electrochemical properties of the electrode were studied by cyclic voltammetry and constant current charge-discharge test.The main content is as follows: 1.Carbon nanotubes (CNTs) were treated by acidizing refluxing with mixed acid (the ratio of hydrochloric acid to nitric acid is 3: 1). By observing its characterization, it can be seen that under the strong oxidation of mixed acid, the CNTs were purified to a certain extent, and the tube bundles were cut off and opened.The internal and external surface area utilization of CNTs was improved. The specific capacitance obtained by acidizing reflux for 4 h at 90 鈩，

本文編號(hào)：1729864