本文關鍵詞：二氧化錳超級電容器電極材料制備及電化學性能研究　出處：《北京交通大學》2017年碩士論文　論文類型：學位論文

  更多相關文章： 超級電容器 材料形貌 MnO_2 石墨烯 PVDF 氮摻雜

【摘要】：作為一種新型儲能體系,超級電容器的快速發(fā)展有望克服鋰離子電池固有局限性。以二氧化錳(MnO_2)為代表的超級電容器電極材料,由于低導電性和低結晶度等缺點,限制了它們在高能量密度超級電容器領域中的應用�，F(xiàn)今主要通過對電極結構的可控制備與制備復合材料提升MnO_2電極材料電學性能。因此,本文選擇MnO_2作為研究對象,通過不同方式進一步提升電學性能并探索相關的儲能機制。本論文的研究內容如下:(1)探究制備條件對電化學性能的影響,通過控制水熱反應條件可控制備二氧化錳電極材料。通過不同表征手段結合電化學性能測試,分析二氧化錳相變過程與反應條件之間的內在聯(lián)系,探究最佳制備方案。通過實驗發(fā)現(xiàn)二氧化錳在反應過程中存在一個α→δ相變的過程。在140 ℃下水熱6小時制備出花狀δ-MnO_2納米球,電流密度為0.5Ag~(-1)時比電容可達192.7Fg~(-1),并且在1Ag~(-1)循環(huán)1000次后比電容保持率為94.6%,表明它是一種具有良好前景的超級電容器電極材料。(2)設計和制造了石墨烯/聚偏二氟乙烯(GO/PVDF)復合粘結劑,提升二氧化錳超級電容器電學性能。相比于物理混合粘結劑,采用石墨烯復合粘結劑制備的二氧化錳電極比電容在0.5 Ag~(-1)電流密度下可達220.1 Fg~(-1)。此外,該電極顯示優(yōu)異的循環(huán)穩(wěn)定性,1 A g~(-1)電流密度下循環(huán)1000次后比電容為198.8 Fg~(-1),電容保持率為90.1%。(3)通過水熱法制備花狀氮摻雜石墨烯/二氧化錳納米復合材料(NG-MnO_2)。所制備的氮摻雜復合材料孔徑約為0.765cm3g~(-1),比表面積為201.8m2g~(-1)。該材料具有優(yōu)異的倍率性能,10Ag~(-1)電流密度下比電容可達189.1 Fg~(-1)。1000次循環(huán)后,比電容保持率為98.3%以上,與活性炭組裝成不對稱電容器后可點亮紅色發(fā)光二極管(LED),具有良好的電學性能。
[Abstract]:As a new energy storage system, the rapid development of supercapacitors is expected to overcome the inherent limitations of lithium ion batteries. Because of low conductivity and low crystallinity and other shortcomings. It limits their application in the field of high energy density supercapacitors. Nowadays, the electrical properties of MnO_2 electrode materials are improved by the controllable preparation and fabrication of composite materials. This paper chooses MnO_2 as the research object. Through different ways to further improve the electrical properties and explore the related mechanisms of energy storage. The research content of this paper is as follows: 1) to explore the preparation conditions on the electrochemical performance. Manganese dioxide electrode materials can be controlled by controlling hydrothermal reaction conditions, and the intrinsic relationship between phase transition process and reaction conditions of manganese dioxide is analyzed by means of different characterization means and electrochemical performance test. To explore the best preparation method. It is found that there is a 偽 in the reaction process of manganese dioxide by experiment. 鈫扵he process of 未 phase transition. The flower-like 未 -MnO _ 2 nanospheres were prepared at 140 鈩，

本文編號：1403017