本文選題：砷摻雜碳納米管　切入點(diǎn)：砷氮共摻雜碳納米管　出處：《中國礦業(yè)大學(xué)》2017年碩士論文

【摘要】：氧還原反應(yīng)(Oxygen Reduction Reaction,ORR)和氧析出反應(yīng)(Oxygen Evolution Reaction,OER)作為能量儲存和轉(zhuǎn)換過程中的兩個(gè)關(guān)鍵電化學(xué)反應(yīng),一直是電催化領(lǐng)域的研究熱點(diǎn)。目前圍繞ORR和OER反應(yīng)所開發(fā)的催化劑多是以Pt、Ru和Ir等貴金屬催化劑為主,并取得一定進(jìn)展。然而,貴金屬儲量少和價(jià)格高等缺點(diǎn),卻使其一直難以規(guī)�；瘧�(yīng)用。近年來大量研究表明新近出現(xiàn)成本低廉的非金屬摻雜碳材料展現(xiàn)出較好的ORR和OER電催化性能,可望取代貴金屬催化劑。為開發(fā)出活性更加優(yōu)異的非金屬摻雜碳催化劑,本文嘗試制備了新型砷摻雜、砷氮共摻雜的碳納米管和氮摻雜有序介孔碳材料,用于ORR和OER的電催化并對其催化機(jī)制進(jìn)行探討。主要內(nèi)容如下:(1)新型砷摻雜碳納米管(As-CNTs)的制備及其電催化性能考察采用化學(xué)氣相沉積法(CVD),將含有三苯基砷的二甲苯溶液在高溫下氣化熱解,制備As-CNTs,并對獲得的As-CNTs結(jié)構(gòu)、組成等進(jìn)行表征分析,結(jié)果表明原子半徑較大的砷原子可以摻入到碳納米管的網(wǎng)絡(luò)結(jié)構(gòu)。電化學(xué)測試表明所制備的As-CNTs在堿性條件下展現(xiàn)出較好的ORR和OER電催化活性,顯示砷原子摻雜能明顯改善碳納米管的ORR和OER電催化活性。同時(shí),密度泛函理論計(jì)算表明砷原子周邊的碳原子的凈電荷由變成了電負(fù)性,且能隙降低,進(jìn)一步從理論上證實(shí)砷原子摻雜有利于提高碳納米管的ORR和OER電催化性能。(2)新型砷氮共摻雜碳納米管(AsN-CNTs)的制備及其電催化性能考察為了進(jìn)一步提高砷摻雜碳材料的催化活性,本文又嘗試合成了砷氮二元共摻雜碳納米管(AsN-CNTs),并對所制備的材料進(jìn)行結(jié)構(gòu)表征和元素含量分析,證實(shí)砷元素和氮元素的成功摻雜。電化學(xué)測試結(jié)果表明:在堿性條件下,AsN-CNTs的ORR電催化活性明顯優(yōu)于氮摻雜碳納米管(N-CNTs),表明As和N原子之間存在協(xié)同作用。同時(shí),砷氮共摻碳納米管還表現(xiàn)出了優(yōu)異的OER催化活性。理論計(jì)算結(jié)果表明砷原子和氮原子周圍的碳原子凈電荷發(fā)生改變,以展現(xiàn)出更多的活性位點(diǎn),且能隙降低,更有利于ORR和OER電催化性能的提高。(3)摻氮碳材料中活性氮物種對ORR和OER催化性能的影響盡管摻氮碳材料在ORR和OER的應(yīng)用已經(jīng)取得了巨大的進(jìn)展,然而,關(guān)于何種氮對ORR的起主要作用一直都沒有定論。為此,本文以廉價(jià)的煙葉為原料,制備氮摻雜有序介孔碳材料(N-OMC),用二氰二胺用來調(diào)節(jié)氮的種類和含量,并在堿性和酸性條件下,同時(shí)對其ORR和OER催化活性進(jìn)行測試分析,結(jié)果顯示:在N-OMC中,吡啶氮和吡咯氮對ORR和OER催化活性的提高起主要作用,這對未來雙功能催化劑的開發(fā)具有指導(dǎo)性意義。
[Abstract]:Oxygen Reduction reaction (ORR) and oxygen precipitation reaction (Oxygen Evolution reaction or er) are two key electrochemical reactions in energy storage and conversion. It has been a research hotspot in the field of electrocatalysis. At present, the catalysts developed around ORR and OER reactions are mainly precious metal catalysts, such as PTR Ru and ir, and some progress has been made. However, there are some disadvantages such as small reserves and high price of precious metals. In recent years, a large number of studies have shown that the low cost nonmetallic doped carbon materials exhibit good electrocatalytic properties of ORR and OER. It is expected to replace noble metal catalysts. In order to develop non-metal doped carbon catalysts with better activity, new arsenic doped, arsenic nitrogen co-doped carbon nanotubes and nitrogen-doped ordered mesoporous carbon materials have been prepared. The main contents of this paper are as follows: (1) preparation of new arsenic doped carbon nanotubes (As-CNTs) and its electrocatalytic properties. Chemical Vapor deposition (CVD) method was used to study the catalytic mechanism of ORR and OER. Benzene solution is pyrolyzed by gasification at high temperature, As-CNTswere prepared, and the structure and composition of the obtained As-CNTs were characterized and analyzed. The results show that arsenic atoms with larger atomic radius can be incorporated into the network structure of CNTs. Electrochemical tests show that the prepared As-CNTs exhibits good ORR and OER electrocatalytic activity under alkaline conditions. The results show that the doping of arsenic atom can obviously improve the ORR and OER electrocatalytic activity of carbon nanotubes. Meanwhile, the density functional theory calculation shows that the net charge of the carbon atom around the arsenic atom changes from electronegativity to electronegativity, and the energy gap decreases. It is further proved that arsenic atom doping is beneficial to the improvement of ORR and OER electrocatalytic properties of carbon nanotubes.) the preparation and electrocatalytic properties of new arsenic-nitrogen co-doped carbon nanotubes (AsN-CNTss) were investigated in order to further improve the catalytic activity of arsenic-doped carbon materials. In this paper, AsN-CNTsO was synthesized, and the structure and elemental content of the prepared materials were analyzed. The electrochemical test results showed that the ORR electrocatalytic activity of AsN-CNTs was obviously superior to that of N-CNTsN doped carbon nanotubes under alkaline conditions, indicating that there was a synergistic effect between as and N atoms. The results of theoretical calculation show that the net charge of carbon atoms around arsenic atom and nitrogen atom changes to show more active sites and the energy gap decreases. The effect of active nitrogen species in nitrogen-doped carbon materials on the catalytic performance of ORR and OER although the application of nitrogen-doped carbon materials in ORR and OER has made great progress, however, There has been no conclusion as to which nitrogen plays a major role in ORR. Therefore, N-doped ordered mesoporous carbon material (N-OMC) was prepared by using cheap tobacco leaves as raw materials. Dicyandiamide was used to regulate the type and content of nitrogen in alkaline and acidic conditions. At the same time, the catalytic activities of ORR and OER were tested and analyzed. The results showed that pyridine nitrogen and pyrrole nitrogen played a major role in the improvement of the catalytic activity of ORR and OER in N-OMC, which was instructive to the development of bifunctional catalysts in the future.
【學(xué)位授予單位】：中國礦業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：O643.36;O646

【參考文獻(xiàn)】

相關(guān)期刊論文 前6條

1 Sijie Guo;Yanmei Yang;Naiyun Liu;Shi Qiao;Hui Huang;Yang Liu;Zhenhui Kang;;One-step synthesis of cobalt,nitrogen-codoped carbon as nonprecious bifunctional electrocatalyst for oxygen reduction and evolution reactions[J];Science Bulletin;2016年01期

2 張開悅;劉偉華;陳暉;張博;劉建國;嚴(yán)川偉;;堿性電解水析氫電極的研究進(jìn)展[J];化工進(jìn)展;2015年10期

3 杜晶晶;李娜;許建雄;許利劍;;電解水析氫電極材料的研究新進(jìn)展[J];功能材料;2015年09期

4 侯明;衣寶廉;;燃料電池技術(shù)發(fā)展現(xiàn)狀與展望[J];電化學(xué);2012年01期

5 劉志祥;錢偉;郭建偉;張杰;王誠;毛宗強(qiáng);;質(zhì)子交換膜燃料電池材料[J];化學(xué)進(jìn)展;2011年Z1期

6 毛宗強(qiáng);;氫能——我國未來的清潔能源[J];化工學(xué)報(bào);2004年S1期

相關(guān)博士學(xué)位論文 前2條

1 丁舟波;電動(dòng)汽車燃料電池系統(tǒng)性能與優(yōu)化設(shè)計(jì)研究[D];湖南大學(xué);2014年

2 張世明;碳基納米復(fù)合結(jié)構(gòu)非貴金屬氧電極反應(yīng)雙功能催化劑[D];武漢大學(xué);2014年

，

本文編號：1654336