【摘要】：異質(zhì)原子摻雜碳材料在電化學(xué)儲(chǔ)能領(lǐng)域的應(yīng)用研究與日俱增,這主要是由于摻雜異質(zhì)原子后可在碳晶格引入更多的缺陷點(diǎn)位及增強(qiáng)電子傳輸特性,從而顯著提升其電化學(xué)性能。例如氮摻雜進(jìn)入石墨的晶格結(jié)構(gòu)后可形成石墨型氮及吡咯、吡啶型氮,不僅可以提高納米碳材料的表面化學(xué)活性,還可對(duì)其電子結(jié)構(gòu)進(jìn)行調(diào)節(jié)。近年來,除了氮,磷元素的摻雜也引起了越來越多的關(guān)注。由于磷的電負(fù)性低于碳的電負(fù)性,且給電子能力遠(yuǎn)強(qiáng)于碳,故磷元素?fù)诫s的碳材料的電化學(xué)活性得到很大的提升。然而,目前為止,合成異質(zhì)原子摻雜碳材料的方法依然非常有挑戰(zhàn)性,亟待開發(fā)出簡(jiǎn)單的新方法。本文中,我們通過一系列方法合成了異質(zhì)原子摻雜碳材料,并系統(tǒng)研究了異質(zhì)原子的摻雜對(duì)材料電化學(xué)性質(zhì)的影響,具體研究?jī)?nèi)容總結(jié)如下:(1)氮摻雜石墨烯的合成及其鈉離子電池性能研究。1、通過在不同溫度下熱解中間相瀝青及雙氰胺,合成了氮摻雜石墨烯,其中中間相瀝青為碳源,雙氰胺為氮源以及模板。2、通過Hummers法合成氧化石墨,并在不同氣氛下高溫還原合成氮摻雜還原氧化石墨烯。兩種方案合成方法簡(jiǎn)單、綠色環(huán)保,無需表面活性劑以及有毒的有機(jī)溶劑。得到的氮摻雜石墨烯由于其獨(dú)特的褶皺結(jié)構(gòu)、大的比表面積及良好的離子電子傳導(dǎo)性能,在鈉離子電池方面展現(xiàn)出較高的可逆容量、良好的循環(huán)穩(wěn)定性,是非常有前景的鈉離子電池負(fù)極材料。(2)磷摻雜石墨烯的合成及其鈉離子電池性能研究。我們利用氧化石墨作為基體材料,三苯基磷作為磷源,超聲混合后在高溫下對(duì)氧化石墨作還原處理,制備出了磷氧共摻雜的還原氧化石墨烯,并且表現(xiàn)出優(yōu)異的儲(chǔ)鈉性能。良好的電化學(xué)性能亦是得益于該電極材料不僅具有大的比表面積及褶皺狀結(jié)構(gòu),而且還受益于磷原子摻雜之后石墨烯材料的電導(dǎo)率提高及其層間距變大等協(xié)同效應(yīng)的影響。
[Abstract]:The application of heteroatom-doped carbon materials in the field of electrochemical energy storage is increasing day by day. This is mainly due to the introduction of more defects in the carbon lattice and the enhancement of electron transport characteristics after doping the heterogeneous atoms, which significantly improves its electrochemical performance. For example, nitrogen doping into the lattice structure of graphite can form graphite-type nitrogen and pyrrole, pyridine-type nitrogen, which can not only improve the surface chemical activity of nano-carbon materials, but also adjust its electronic structure. In recent years, in addition to nitrogen, phosphorus doping has also attracted more and more attention. Because the electronegativity of phosphorus is lower than that of carbon, and the electron ability is much stronger than that of carbon, the electrochemical activity of carbon doped with phosphorus is greatly improved. However, so far, the method of synthesizing heterogeneous atom doped carbon materials is still very challenging, and a new simple method is urgently needed to be developed. In this paper, we synthesized heterogeneous atom doped carbon material by a series of methods, and systematically studied the influence of heterogeneous atom doping on the electrochemical properties of the material. The specific research contents are summarized as follows: (1) the synthesis of nitrogen-doped graphene and the performance of sodium ion battery. 1. Nitrogen doped graphene was synthesized by pyrolysis of mesophase pitch and dicyandiamide at different temperatures, and its mesophase pitch was used as carbon source. Graphite oxide was synthesized by Hummers method with dicyandiamide as nitrogen source and template. The two methods are simple, green, no surfactant and toxic organic solvent. Because of its unique fold structure, large specific surface area and good ionic electron conductivity, the nitrogen-doped graphene shows high reversible capacity and good cycling stability in sodium ion batteries. It is a promising anode material for sodium ion batteries. (2) Synthesis of phosphate-doped graphene and study on the performance of sodium ion batteries. In this paper, graphite oxide was used as matrix material, triphenyl phosphorus as phosphorus source. After ultrasonic mixing, graphite oxide was reduced at high temperature to prepare reductive graphene, which was co-doped with phosphorus and oxygen, and showed excellent sodium storage properties. The good electrochemical performance is also due to not only the large specific surface area and fold structure of the electrode, but also the synergistic effects such as the increase of the conductivity and the increase of the interlayer spacing of the graphene materials doped with phosphorus atoms.
【學(xué)位授予單位】：中國(guó)礦業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TQ127.11;TM912

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 陳旭;何大平;木士春;;摻氮石墨烯研究[J];化學(xué)進(jìn)展;2013年08期

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本文編號(hào)：2201035