CN108630442A - 一种c3n4增强型超级电容器的制备方法 - Google Patents
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- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
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Abstract
本发明公开了一种C3N4增强型超级电容器的制备方法，该方法制备了三维结构的C3N4，以此作为复合电极的电极材料，与电解质、集流体组装成超级电容器。该方法利用了三维的C3N4结构高比表面积的特性，增大赝电容材料聚3，4‑乙烯二氧噻吩/聚苯乙烯磺酸盐(PEDOT)的有效接触面积，同时，利用PEDOT弥补C3N4电导率低的不足，进而提高超级电容器的比电容值，及循环效率，并且制备方法简单。
Description
技术领域
本发明涉及一种增强型超级电容器的制备方法，特别涉及一种三维结构的类石墨烯相C3N4(g-C3N4)，以提高电极材料比表面积和电荷容量的方法。
背景技术
随着环境污染日益严重，急需一种清洁又高效的能源装置代替化石燃料。而超级电容器作为一种新型能源存储设备，近年来受到了广泛的关注。与传统能源存储设备相比，它具有更高的功率密度和更好的循环稳定性。根据其在储能过程中所依据的机理不同，主要分为双电层电容，法拉第电容及混合电容。其中双电层电容的储能模式主要取决于电解液离子在电极表面的吸附过程，属于简单的物理机制，其存储能量的多少取决于电极材料的选择，即具有电解液离子可接近的高比表面积的材料。
近年来，g-C3N4由于具有与石墨烯相似的原子结构以及超高的比表面积，成为化学和材料科学领域的研究热点，尤其是在光催化领域有优异的表现。目前，关于C3N4的制备方法主要有高温高压法，气相沉积法，液相电沉积法等。但这些方法得到的g-C3N4主要为二维结构，制备过程中存在大量的缺陷态，g-C3N4高比表面积的优势并没有充分发挥。
发明内容
本发明的目的是提供一种C3N4增强型超级电容器的制备方法，该方法能制备一种C3N4增强型超级电容器。该方法是一种三维C3N4结构的制备方法，并将其应用在超级电容器，以三维结构达到增大比表面积和电荷容量的目的。
本发明包括以下步骤：
1)、制备C3N4粉末：
用煅烧尿素法制备类石墨烯结构的C3N4，调整g-C3N4分子结构大小以及微观片层结构厚度。
2)、制备C3N4气凝胶：
处理C3N4，加入KOH，让C3N4由纳米片结构变成纳米线结构；再经过透析处理去除多余的氢氧根离子；最后经过冷冻干燥去除水，得到三维C3N4气凝胶结构；
3)、制备C3N4@PEDOT：PSS的三维气凝胶：
步骤2)处理后的C3N4提供高的比表面积及三维骨架结构，PEDOT:PSS提供高的赝电容电荷容量，将C3N4和PEDOT：PSS混合，经过冷冻干燥去除溶剂水，得到三维的C3N4@PEDOT：PSS气凝胶结构。
4)、将C3N4@PEDOT：PSS/泡沫镍电极材料进行压片、切割、封装制备能量存储设备电极。
本发明的有益效果是：
本发明将二维的g-C3N4经过处理变成三维结构，这种材料具有更大的比表面积，更高的电荷容量。用这种材料制备出的增强型C3N4超级电容器与传统超级电容器相比，有更高的比电容值，而且循环效率比较稳定。具有工艺简单，操作方便的特点。纯PEDOT为119F/g；混合后(PEDOT:g-C3N4为80:20)为180F/g。提高了51.2％。
具体实施方式
本发明包括以下步骤
1)、制备C3N4粉末：
称取20g尿素放置在坩埚中，将坩埚放在马弗炉中，设置程序升温，以每分钟10℃的速率从室温升至550℃，并且在550℃维持2h，冷却至室温。获得C3N4粉末。
2)、制备三维C3N4气凝胶：
将500mg的C3N4粉末加入20ml的3M的KOH中，加热到60℃加热搅拌12h。将搅拌后的液体超声两个小时，缓慢倒入截留分子量3500透析袋中，透析直至到中性。最后在冷冻干燥机中进行冷冻干燥，得到三维C3N4气凝胶。
3)制备C3N4@PEDOT：PSS的三维气凝胶
量取5ml透析后的浓度为5mg/ml的C3N4溶液与量取10ml的PEDOT：PSS(聚3，4-乙烯二氧噻吩/聚苯乙烯磺酸盐)(ALDRICH 1.0wt％in H2O)混合搅拌均匀，超声处理30分钟后。在冷冻干燥机中进行冷冻干燥，得到C3N4@PEDOT：PSS的三维气凝胶。
4)、超级电容器的制备：
对C3N4/泡沫镍电极进行压片切割，制成电极。
名词解释：
C3N4是这个材料的分子式，g-C3N4是指具有石墨烯结构的C3N4。
PEDOT中文是：聚3，4-乙烯二氧噻吩。
PSS中文是：聚苯乙烯磺酸盐
PEDOT:PSS中文是：聚3，4-乙烯二氧噻吩/聚苯乙烯磺酸盐。
C3N4@PEDOT：PSS中的“@”中文是混合的意思。
Claims (1)
1.一种C3N4增强型超级电容器的制备，该方法包括以下步骤：
1)制备C3N4粉末：
用煅烧尿素法制备类石墨烯结构的C3N4，调整g-C3N4分子结构大小以及微观片层结构厚度；
2)制备C3N4气凝胶：
处理C3N4，加入KOH，让C3N4由纳米片结构变成纳米线结构；再经过透析处理去除多余的氢氧根离子；最后经过冷冻干燥去除水，得到三维C3N4气凝胶结构；
3)制备C3N4@PEDOT：PSS的三维气凝胶：
步骤2)处理后的C3N4提供高的比表面积及三维骨架结构，PEDOT:PSS提供高的赝电容电荷容量，将C3N4和PEDOT：PSS混合，经过冷冻干燥去除溶剂水，得到三维的C3N4@PEDOT：PSS气凝胶结构；
4)将C3N4@PEDOT：PSS/泡沫镍电极材料进行压片、切割、封装制备能量存储设备电极。
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111628092A (zh) * | 2019-02-28 | 2020-09-04 | Tcl集团股份有限公司 | 一种量子点发光二极管及其制备方法 |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103285920A (zh) * | 2013-05-27 | 2013-09-11 | 东华大学 | 一种三维纤维基气凝胶催化剂载体及其制备方法 |
| CN103745836A (zh) * | 2013-12-29 | 2014-04-23 | 渤海大学 | g-C3N4/碳量子点复合电极的制备方法 |
| CN104852013A (zh) * | 2015-03-17 | 2015-08-19 | 中国科学院广州能源研究所 | 一种基于水性粘结剂的三维电极极片的制备方法 |
| CN105336498A (zh) * | 2015-10-21 | 2016-02-17 | 江南大学 | 一种新型稳定的g-C3N4/NiO光电阴极的制备方法 |
| CN103219503B (zh) * | 2013-03-12 | 2016-02-24 | 北京理工大学 | 一种复合电极材料及其制备方法 |
| CN105810442A (zh) * | 2016-03-16 | 2016-07-27 | 长春工业大学 | 一种g-C3N4增强型太阳能电池的制造方法 |
| CN105826088A (zh) * | 2016-05-10 | 2016-08-03 | 复旦大学 | 一种具有多级结构的碳气凝胶/二氧化锰复合电极材料及其制备方法 |
| US20160233487A1 (en) * | 2015-02-06 | 2016-08-11 | Mitsubishi Chemical Corporation | Pnictide containing catalysts for electrochemical conversion reactions and methods of use |
| CN106582768A (zh) * | 2016-12-29 | 2017-04-26 | 南京工业大学 | 一种二维、三维载体增强氮化碳光催化材料的制备方法 |
| CN106732738A (zh) * | 2017-02-15 | 2017-05-31 | 东华大学 | 一种石墨烯/g‑C3N4三维网络复合薄膜及其制备和应用 |
| CN107958791A (zh) * | 2017-02-23 | 2018-04-24 | 中国科学院深圳先进技术研究院 | 一种三维材料、其制备方法及超级电容器用电极 |
-
2018
- 2018-04-28 CN CN201810397255.4A patent/CN108630442B/zh not_active Expired - Fee Related
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103219503B (zh) * | 2013-03-12 | 2016-02-24 | 北京理工大学 | 一种复合电极材料及其制备方法 |
| CN103285920A (zh) * | 2013-05-27 | 2013-09-11 | 东华大学 | 一种三维纤维基气凝胶催化剂载体及其制备方法 |
| CN103745836A (zh) * | 2013-12-29 | 2014-04-23 | 渤海大学 | g-C3N4/碳量子点复合电极的制备方法 |
| US20160233487A1 (en) * | 2015-02-06 | 2016-08-11 | Mitsubishi Chemical Corporation | Pnictide containing catalysts for electrochemical conversion reactions and methods of use |
| CN104852013A (zh) * | 2015-03-17 | 2015-08-19 | 中国科学院广州能源研究所 | 一种基于水性粘结剂的三维电极极片的制备方法 |
| CN105336498A (zh) * | 2015-10-21 | 2016-02-17 | 江南大学 | 一种新型稳定的g-C3N4/NiO光电阴极的制备方法 |
| CN105810442A (zh) * | 2016-03-16 | 2016-07-27 | 长春工业大学 | 一种g-C3N4增强型太阳能电池的制造方法 |
| CN105826088A (zh) * | 2016-05-10 | 2016-08-03 | 复旦大学 | 一种具有多级结构的碳气凝胶/二氧化锰复合电极材料及其制备方法 |
| CN106582768A (zh) * | 2016-12-29 | 2017-04-26 | 南京工业大学 | 一种二维、三维载体增强氮化碳光催化材料的制备方法 |
| CN106732738A (zh) * | 2017-02-15 | 2017-05-31 | 东华大学 | 一种石墨烯/g‑C3N4三维网络复合薄膜及其制备和应用 |
| CN107958791A (zh) * | 2017-02-23 | 2018-04-24 | 中国科学院深圳先进技术研究院 | 一种三维材料、其制备方法及超级电容器用电极 |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111628092A (zh) * | 2019-02-28 | 2020-09-04 | Tcl集团股份有限公司 | 一种量子点发光二极管及其制备方法 |
| CN111628092B (zh) * | 2019-02-28 | 2022-01-18 | Tcl科技集团股份有限公司 | 一种量子点发光二极管及其制备方法 |
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