本文選題：功能化碳材料　切入點：超級電容器　出處：《華中農(nóng)業(yè)大學》2015年博士論文　論文類型：學位論文

【摘要】：超級電容器作為一種新型儲能裝置,集高能量密度、高功率密度、長使用壽命等特性于一身,是一種極具應(yīng)用潛力的綠色能源,開展超級電容器的研究工作具有非常大的現(xiàn)實意義和社會效益。本論文主要研究了超級電容器的關(guān)鍵組成部分-電極材料。以碳材料為電極基體材料,選用不同的制備方法,改進其組成成分和微觀結(jié)構(gòu),獲得了多種類型的具有高電容量的功能化碳電極材料。采用各種表征手段對其形貌和結(jié)構(gòu)進行表征,同時利用循環(huán)伏安、恒電流充放電、交流阻抗等方法測試材料相應(yīng)的電化學性能。對相關(guān)的形成機理和結(jié)果進行了探討分析,旨在得到具備優(yōu)異電化學性能的碳電極材料。主要研究工作如下:1.以nano-Ca CO3為硬模板,三聚氰胺甲醛樹脂(MF)為碳源和氮源,制備出新型氮摻雜多級孔碳材料。通過改變模板加入量和碳化溫度,可以得到不同形貌和不同含氮量的多孔碳。含氮量高達20.9 wt%,具有豐富的孔洞結(jié)構(gòu)和高的比表面積(834 m2 g-1)。電化學測試結(jié)果表明:900℃碳化條件下,模板比例高的樣品具有最高的電容值283 F g-1(1 A g-1),此外,電極還展示了優(yōu)異的倍率性能和長時間充放電循環(huán)穩(wěn)定性。該方法簡便,模板成本低,為合成多孔碳材料提供了新的思路。2、通過簡單的水熱法制備了石墨烯/Ni(OH)2復(fù)合電極材料,Ni(OH)2呈現(xiàn)出納米線和納米片兩種形式,均勻的負載在石墨烯片上,包括α和β兩種晶相。我們對其形成機理進行了詳細的探討和分析。與石墨烯和純Ni(OH)2材料相比,復(fù)合材料具有更高的比電容值(970 F g-1),優(yōu)良的倍率性能和較好的穩(wěn)定性。其原因總結(jié)如下:Ni(OH)2具有優(yōu)異的贗電容性質(zhì),與石墨烯復(fù)合后可以大大提高材料的整體電容值;石墨烯作為結(jié)構(gòu)支撐材料,避免了Ni(OH)2在充放電過程中發(fā)生嚴重的聚集,增加電解液離子與活性位點的接觸面積,提高材料的導(dǎo)電性;石墨烯的存在有效地改善了材料的倍率性能和穩(wěn)定性。3、以Si O2球作為間隔物,離子液體(IL)作為結(jié)構(gòu)導(dǎo)向劑,采用低溫水熱法合成了功能化的3D分級多孔石墨烯材料,該材料具有豐富的大孔和介孔,比表面積高達341 m2 g-1。Si O引入為材料提供了大量開放性的大孔,IL附著在石墨烯片上可以防止其在后處理過程中發(fā)生堆疊,并且改善石墨烯的導(dǎo)電性。這種獨特的3D分級孔結(jié)構(gòu)促進了電解液離子的擴散和電荷轉(zhuǎn)移,繼而提高了材料的利用效率。低溫處理保留的大量含氧官能團,提高了材料的親水性,而且在充放電過程中產(chǎn)生贗電容。實驗結(jié)果表明,該材料具有高的比電容值,好的倍率性能和優(yōu)異的循環(huán)穩(wěn)定性。此外,組裝的對稱兩電極電容器擁有13.3 k W kg-1的高功率密度,展現(xiàn)了非常大的應(yīng)用潛力。同時,我們制備的功能化3D多孔石墨烯有望應(yīng)用于其他領(lǐng)域,我們所用的制備方法能夠?qū)ζ渌牧系脑O(shè)計調(diào)控起到借鑒和指導(dǎo)作用。
[Abstract]:As a new type of energy storage device, supercapacitor is a kind of green energy with high energy density, high power density and long service life. The research work of supercapacitor has great practical significance and social benefit. In this paper, the key component of supercapacitor, electrode material, is studied. Carbon material is used as electrode matrix material, and different preparation methods are selected. Various kinds of functional carbon electrode materials with high capacitance were obtained by improving their composition and microstructure. The morphology and structure were characterized by various means of characterization, at the same time, cyclic voltammetry, constant current charge and discharge were used. Electrochemical properties of the materials were measured by AC impedance method. The formation mechanism and results were discussed and analyzed to obtain carbon electrode materials with excellent electrochemical properties. The main research work is as follows: 1. Using nano-Ca CO3 as hard template, Melamine formaldehyde resin (MFF) was used as carbon source and nitrogen source to prepare a new type of nitrogen-doped multiporous carbon material. By changing the amount of template and carbonation temperature, Porous carbon with different morphology and nitrogen content can be obtained. The nitrogen content is up to 20.9 wts. it has abundant pore structure and high specific surface area of 834 m2 g-1.The electrochemical test results show that under the carbonation condition of 1: 900 鈩，

本文編號：1597262