本文關(guān)鍵詞：基于石墨烯紙的超級(jí)電容儲(chǔ)能特性研究　出處：《浙江大學(xué)》2015年碩士論文　論文類(lèi)型：學(xué)位論文

  更多相關(guān)文章： 石墨烯紙 超級(jí)電容器 常壓輝光放電掃描正柱區(qū)等離子體 垂直石墨烯 比電容 功率密度

【摘要】：超級(jí)電容器是一種新型的電化學(xué)儲(chǔ)能元件,擁有著比鋰離子電池更高的功率密度和循環(huán)壽命,而被廣泛研究。石墨烯紙具有良好的自支撐能力及導(dǎo)電性,在作為超級(jí)電容器電極材料時(shí),不再需要粘結(jié)劑和導(dǎo)電劑的加入,正成為當(dāng)今的超級(jí)電容器電極材料的研究熱點(diǎn)。 本文首先采用化學(xué)還原法制備了石墨烯,并利用真空抽濾法得到石墨烯紙,然后對(duì)其進(jìn)行超級(jí)電容儲(chǔ)能性能測(cè)試分析,發(fā)現(xiàn)在較低的掃速下,該種石墨烯紙表現(xiàn)出了良好的電容性能。在水系電解液中測(cè)得10mVs-1時(shí)的比電容達(dá)到了150Fg1。但是,隨著掃速的增大,表現(xiàn)出了明顯的電容衰減,在1000mV S-1時(shí),比電容只有71.5F g-1。這說(shuō)明真空抽濾得到的石墨烯紙內(nèi)部石墨烯片的緊密堆疊,降低了石墨烯紙的比表面積利用率,而影響了其電容性能。 針對(duì)化學(xué)還原石墨烯紙堆疊緊密的不足,提出了以常壓直流輝光放電掃描正柱區(qū)等離子體還原得到石墨烯紙(P-rGO)的方法。經(jīng)材料表征發(fā)現(xiàn),P-rGO具有良好的孔隙結(jié)構(gòu),擁有大量的開(kāi)放性通道,且具有優(yōu)異的流體滲流性能。相比于傳統(tǒng)化學(xué)法制備的石墨烯紙(C-rGO),擁有著更大的比電容,在有機(jī)體系測(cè)試得到,10mV s-1時(shí)P-rGO的比電容為181.4F g1,而傳統(tǒng)方法制備的石墨烯紙只有為120F g-1。P-rGO還表現(xiàn)出了更好的倍率性能。當(dāng)電流密度從1A-1增加到50A g-1時(shí),P-rGO的比電容從162F g-1只降到125F g-1,比電容的保持率為77%,而傳統(tǒng)方法制備的石墨烯紙的比電容保持率只有18%,要遠(yuǎn)遠(yuǎn)小于P-rGO。 為了獲得高倍率性能的石墨烯紙超級(jí)電容器,利用垂直石墨烯的高導(dǎo)電率及多暴露邊緣等特點(diǎn),對(duì)集流體與活性材料之間進(jìn)行橋接,可為集流體和活性材料界面之間提供大量的接觸點(diǎn),從而減少了該界面間的電荷傳輸路徑,減小了界面的接觸電阻。結(jié)果顯示,通過(guò)垂直石墨烯橋接集流體與活性材料的石墨烯紙超級(jí)電容器擁有良好的倍率性能,當(dāng)掃速?gòu)?0mV s-1增加到1000mV s-1,依然能夠保持約90%的比電容。且當(dāng)電流密度達(dá)到600A g-1時(shí),可以獲得超高的功率密度為112.6kW kg-1,同時(shí)仍能保持130F g-1的高比電容值。
[Abstract]:Supercapacitor is a new type of electrochemical energy storage element, which has higher power density and cycle life than Li-ion battery, and has been widely studied. Graphene paper has good self-supporting ability and electrical conductivity. As electrode materials of supercapacitors, the binder and conductive agent are no longer needed, which is becoming the research hotspot of electrode materials for supercapacitors. In this paper, graphene was prepared by chemical reduction method, and the graphene paper was obtained by vacuum filtration. Then the energy storage performance of super capacitor was tested and analyzed, and it was found that at low sweep speed. This kind of graphene paper shows good capacitance performance. The specific capacitance of 10mVs-1 measured in aqueous electrolyte reaches 150Fg1.However, with the increase of sweep speed. At 1000mV S-1, the specific capacitance is only 71.5 F g -1, which indicates the compact stacking of graphene sheets inside graphene paper by vacuum filtration. The specific surface area utilization ratio of graphene paper is reduced, and its capacitance performance is affected. In order to overcome the shortage of chemical reduction graphene paper stack, a method of plasma reduction of graphene paper by normal pressure DC glow discharge scanning positive column plasma reduction was proposed, which was characterized by material. P-rGO has a good pore structure, a large number of open channels, and excellent fluid percolation performance, compared with the traditional chemical method of graphene paper preparation C-rGO. With larger specific capacitance, the specific capacitance of P-rGO was 181.4 F / g1 when the organic system was tested with 10mV s ~ (-1). However, the graphene paper prepared by the traditional method showed better performance when the current density was increased from 1A ~ (-1) to 50 A ~ (-1) g ~ (-1). The specific capacitance of P-rGO was only reduced from 162 F g -1 to 125 F g -1, and the specific capacitance retention rate was 77%, while the specific capacitance retention rate of conventional graphene paper was only 18%. It is much smaller than P-rGO. In order to obtain graphene paper supercapacitors with high rate performance, the high conductivity and multiple exposed edges of vertical graphene were used to bridge the current collection with active materials. It can provide a large number of contact points between the interface of the collector and the active material, thus reducing the charge transfer path between the interface and the contact resistance of the interface. The graphene paper supercapacitors connected with active materials by vertical graphene bridging have good rate performance, when the sweep speed is increased from 20mV s-1 to 1000mV s-1. When the current density reaches 600A g ~ (-1), a high power density of 112.6kW kg-1 can be obtained. At the same time, the high specific capacitance of 130 F g -1 can be maintained.
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：TM53

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 張文亮;丘明;來(lái)小康;;儲(chǔ)能技術(shù)在電力系統(tǒng)中的應(yīng)用[J];電網(wǎng)技術(shù);2008年07期

2 董麗芳;劉為遠(yuǎn);楊玉杰;王帥;嵇亞飛;;大氣壓等離子體炬電子密度的光譜診斷[J];物理學(xué)報(bào);2011年04期

3 Thang Ngoc Cong;;Progress in electrical energy storage system:A critical review[J];Progress in Natural Science;2009年03期

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本文編號(hào)：1366455