【摘要】：隨著可穿戴、輕薄和柔性電子產(chǎn)品的迅速發(fā)展,開(kāi)發(fā)具有高功率、高能量密度的柔性儲(chǔ)能器件已經(jīng)成為儲(chǔ)能領(lǐng)域的研究熱點(diǎn)。然而,常規(guī)的電極制備需要加入導(dǎo)電劑、粘結(jié)劑和金屬集流體。其中,導(dǎo)電劑和粘結(jié)劑是非活性成分,會(huì)降低電極的比容量,而金屬集流體則會(huì)降低電極的整體能量密度和機(jī)械柔性,導(dǎo)致傳統(tǒng)的儲(chǔ)能器件無(wú)法滿足柔性電子設(shè)備的要求。因此,設(shè)計(jì)和開(kāi)發(fā)具有高比容量、質(zhì)輕、自支撐的柔性電極材料是發(fā)展柔性儲(chǔ)能器件的關(guān)鍵所在。目前,柔性電極材料遇到的瓶頸,主要體現(xiàn)在以下兩個(gè)方面:1)材料制備方法復(fù)雜,成本較高;2)電池的電化學(xué)性能仍未達(dá)到傳統(tǒng)鋰離子電池水平,無(wú)法滿足實(shí)際應(yīng)用的要求。針對(duì)上述問(wèn)題,本論文設(shè)計(jì)、開(kāi)發(fā)了兩種兼具柔性和三維多孔結(jié)構(gòu)的氮摻雜網(wǎng)狀碳材料,研究了其在氧氣還原電催化(ORR)和柔性鋰離子電池電極材料方面的應(yīng)用,并探究其結(jié)構(gòu)與性能之間的關(guān)系。具體工作如下:(1)以三聚氰胺泡沫為前驅(qū)體,采用預(yù)氧化和高溫?zé)峤鈨刹椒ㄖ苽淞艘环N多孔氮摻雜碳泡沫(NCFs)�？疾炝祟A(yù)氧化過(guò)程及溫度(250,300℃)對(duì)NCFs形貌、結(jié)構(gòu)和性能的影響。形貌和結(jié)構(gòu)表征顯示,NCFs碳骨架具有較高的石墨化程度和豐富的多級(jí)孔結(jié)構(gòu),比表面積可以達(dá)到980 m2 g~(-1)。力學(xué)性能測(cè)試結(jié)果表明,NCFs在80%的壓縮形變下能回復(fù)到原狀而不發(fā)生任何塑性形變,具有優(yōu)異的彈性性能。NCF-300~(-1)000用作ORR催化電極時(shí),在堿性介質(zhì)中表現(xiàn)出優(yōu)越的催化活性,起始電位與商業(yè)化Pt/C催化劑相當(dāng)。同時(shí),它還具有優(yōu)于Pt/C催化劑的循環(huán)穩(wěn)定性和抗甲醇中毒性。如此優(yōu)異的電催化性能主要?dú)w功于NCFs的多級(jí)孔結(jié)構(gòu)提供了豐富的催化活性位點(diǎn)以及三維石墨化碳結(jié)構(gòu)保證了優(yōu)越的電荷傳遞通道。(2)采用簡(jiǎn)單的壓力輔助熱解法,制備了一種兼具柔性和高密度的氮摻雜碳紙(NCPs)。考察了壓力大小(600,400,200和0 kPa)對(duì)NCPs結(jié)構(gòu)和性能的影響。研究發(fā)現(xiàn),隨著壓力的增大,NCP的三維網(wǎng)狀結(jié)構(gòu)越來(lái)越密集,密度和導(dǎo)電性逐漸升高。三點(diǎn)彎曲測(cè)試結(jié)果顯示,NCPs具有優(yōu)異的機(jī)械柔性。將NCP-600k直接用于鋰電池負(fù)極材料,表現(xiàn)出良好的循環(huán)性能和倍率性能。在0.05和0.5 A g~(-1)的電流密度下循環(huán)200圈,NCP-600k的放電比容量分別為480和329.8 mA h g~(-1);甚至在8.0 A g~(-1)電流密度下循環(huán)500圈,放電比容量仍然能夠保留126.5 mA h g~(-1),保留率可以達(dá)到98.8%。如此優(yōu)異的電化學(xué)性能源于NCPs具有良好的三維導(dǎo)電網(wǎng)絡(luò),促進(jìn)了電荷的高效傳遞;以及碳纖維骨架上的多孔結(jié)構(gòu)和氮原子的摻雜提供了豐富的儲(chǔ)鋰活性位點(diǎn),提高了鋰離子的存儲(chǔ)能力。
[Abstract]:With the rapid development of wearable, thin and flexible electronic products, the development of flexible energy storage devices with high power and high energy density has become a research hotspot in the field of energy storage. However, conventional electrode preparation requires the addition of conductors, binders, and metallic fluid traps. Among them, the conductive agent and binder are inactive components, which will reduce the specific capacity of the electrode, while the metal collector will reduce the overall energy density and mechanical flexibility of the electrode, resulting in the traditional energy storage device can not meet the requirements of flexible electronic equipment. Therefore, the design and development of flexible electrode materials with high specific capacity, light weight and self support is the key to the development of flexible energy storage devices. At present, the bottleneck of flexible electrode material is mainly reflected in the following two aspects: 1) the preparation method of the material is complex and the cost is high. The electrochemical performance of the battery is still not up to the level of the traditional lithium ion battery, which can not meet the requirements of practical application. In order to solve the above problems, two kinds of nitrogen-doped reticular carbon materials with flexible and three-dimensional porous structure were designed and developed in this paper. The applications of these materials in oxygen reduction electrocatalytic (ORR) and flexible lithium ion battery electrode materials were studied. The relationship between structure and performance is explored. The main works are as follows: (1) using melamine foam as precursor, a porous nitrogen-doped carbon foam (NCFs). Was prepared by pre-oxidation and pyrolysis at high temperature. The effects of preoxidation process and temperature (250300 鈩，

本文編號(hào)：2141138