Preparation and properties of flexible supercapacitor based on biochar and solid gel-electrolyte

doi:10.11949/0438-1157.20190162

Abstract

Abstract:

In our present work, a typical biomass, maize straw was used as precursor to prepare porous biochar under high temperature followed with etching by KOH solution. The prepared biochar was characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy (Raman). The specific surface area of as-prepared biochar was calculated by the Brunauer-Emmett-Teller (BET) method. Under the optimal conditions, the specific surface area can reach 1228 m2·g^-1. Then the as-prepared biochar was employed as electrode materials to fabricate the flexible supercapacitor cooperating with the H₂SO₄/PVA gel as electrolyte. The electrochemical capacitance properties of the obtained supercapacitors were tested by cyclic voltammetry (CV) constant current charge-discharge (CD) and AC impedance spectroscopy (EIS) measurements in a two-electrode system. The results showed that the specific capacity reaches 125 F·g^-1 when the current density is 1.0 A·g^-1. Noteworthily, the fabricated supercapacitor demonstrates the perfectly flexibility and stability that the capacitance retention kept at 93.5% under different bending angles (from 0° to 180°) at a constant current density of 1.0 A·g^-1. Furthermore, the flexible supercapacitor also exhibits a satisfied long-term stability performance of 95.6% capacitance retention and 94.9% coulombic efficiency under 180° bending angle through 500 cycles. These very attractive mechanical properties and electrochemical performances enable this flexible supercapacitor to present a great potential for wearable devices as energy storage equipment and open up new avenues to high-value materials from waste maize straw.

Key words: maize straw, biochar, solid gel electrolyte, flexibility, supercapacitor

摘要：

利用固体农业废弃物玉米秸秆作为原料，经高温煅烧，KOH刻蚀获得具有较大比表面积的多孔生物炭材料，并采用粉末X射线衍射仪(XRD)、场发射扫描电镜(FE-SEM)、红外光谱(FT-IR)、拉曼光谱(Raman)以及比表面积和孔径分析仪(BET)等表征手段，研究其物理、化学结构和微观形貌。结果表明，所制备的生物炭材料具有发达的“微孔-中孔-大孔”三维贯通多级孔道结构，比表面积高达1228 m2·g^-1。将其作为电极材料，与H₂SO₄/PVA凝胶电解质可组装成为具有柔性的全固态超级电容器。利用循环伏安测试(CV)、恒电流充放电(GCD)以及交流阻抗测试(EIS)对柔性超级电容器电化学性能进行了测试。在电流密度为1.0 A·g^-1的条件下，其比容量可达125 F·g^-1。该器件具有良好的机械柔性和电化学稳定性，将其从0°弯曲至180°的过程中，比电容保持率约为93.5%；以不同弯曲角度将其连续弯折100次后，仍能保持较高的比电容。此外，在弯折角度180°、充放电电流密度为5.0 A·g^-1 的条件下经过500次循环充放电后，比电容值保持率约为95.6%，库仑效率约为94.9%。说明所制备的柔性超级电容器具有优异的充放电性能和长效循环稳定性。作为一种柔性、质轻、便携的储能装置，在可穿戴电子器件领域内具有潜在应用价值。同时该方法也为固体农业废弃物玉米秸秆的高附加值转化利用和新型绿色能源器件创新研制提供了新的技术途径。

关键词: 玉米秸秆, 生物炭, 固态凝胶电解质, 柔性, 超级电容器

CLC Number:

TQ 031.2

Xinghai YU, Qiliang LUO, Jian PAN, Yuqi HAN, Qifeng ZHANG. Preparation and properties of flexible supercapacitor based on biochar and solid gel-electrolyte[J]. CIESC Journal, 2019, 70(9): 3590-3600.

禹兴海, 罗齐良, 潘剑, 韩玉琦, 张奇峰. 一种生物炭基柔性固态超级电容器的制备及性能研究[J]. 化工学报, 2019, 70(9): 3590-3600.

Figures/Tables 9

Fig.1 SEM images of maize straw power [(a),(b)] and biochar (BC) activated by KOH [(c)—(f)]

Fig.2 Nitrogen adsorption-desorption isotherms and pore size distribution curves of biochar

Table 1 Specific surface area and porosity parameters of biochar at different activated conditions.

Sample

(m _C∶m _KOH)

BET surface, S _BET/(m2·g^-1)

Total volume in pores,

V _Total/(cm3·g^-1)

DFT pore

size/nm

Fig.3 XRD pattern (a), FT-IR spectra (b) and Raman spectra (c) of biochar

Fig.4 Cyclic voltammetry curves of assembled flexible capacitor at various sweep rates and charge/discharge curves at various current

Fig.5 Electrochemical impedance spectra (a) and specific capacitance at different current density (b)

Fig.6 Cyclic voltammetry curves of flexible capacitor for different curvatures and capacitance retention at different bending angles

Fig.7 Specific capacitance of flexible capacitor under 100 bending cycles at 5.0 A·g-1 current density

Fig.8 Long-term cycling performance of flexible capacitor at current density of 5.0 A·g-1 under 180° bending angle (Inset is charge-discharge curves of the last 20 cycles)

References 46

1	Zhang Q F , Uchaker E , Candelaria S L , et al . Nanomaterials for energy conversion and storage[J]. Chem. Soc. Rev., 2013, 42(7): 3127-3171.
2	刘明贤, 缪灵, 陆文静, 等 . 多孔碳材料的设计合成及其在能源存储与转换领域中的应用[J]. 科学通报, 2017, 62(6): 590-605.
	Liu M X , Miao L , Lu W J , et al . Porous carbon materials: design, synthesis and applications in energy storage and conversion devices[J]. Chin. Sci. Bull., 2017, 62(6): 590-605.
3	Chen X L , Qiu L B , Peng H S , et al . Novel electric double-layer capacitor with a coaxial fiber structure[J]. Adv. Mater., 2013, 25(44): 6436-6441.
4	Beidaghi M , Gogotsi Y . Capacitive energy storage in micro-scale devices: recent advances in design and fabrication of micro-supercapacitors[J]. Energy & Environ. Sci., 2014, 7(3): 867-884.
5	Bae J , Song M K , Park Y J , et al . Fiber supercapacitors made of nanowire-fiber hybrid structures for wearable/flexible energy storage[J]. Angew. Chem. Int. Ed., 2011, 50(7): 1683-1687.
6	Yan J , Qian W , Tong W , et al . Recent advances in design and fabrication of electrochemical supercapacitors with high energy densities[J]. Adv. Energy. Mater., 2014, 4(4): 1300816.
7	Cheng Y W , Zhang H B , Lu S T , et al . Flexible asymmetric supercapacitors with high energy and high power density in aqueous electrolytes[J]. Nanoscale, 2013, 5(3): 1067-1073.
8	Kötz R , Carlen M . Principles and applications of electrochemical capacitors[J]. Electrochimica Acta, 2000, 45: 2483-2498.
9	Wang Y G , Song Y F , Xia Y Y . Electrochemical capacitors: mechanism, materials, systems, characterization and applications[J]. Chem. Soc. Rev., 2016, 45(21): 5925-5950.
10	Conway B E , Pell W G . Double-layer and pseudocapacitance types of electrochemical capacitors and their applications to the development of hybrid devices[J]. J.Solid.State.Electr., 2003, 7(9): 637-644.
11	Sharma P , Bhatti T S . A review on electrochemical double-layer capacitors[J]. Energy. Convers. Manage, 2010, 51(12): 2901-2912.
12	Lu Q , Chen J G , Xiao J Q . Nanostructured electrodes for high-performance pseudocapacitors[J]. Angew. Chem. Int. Ed., 2013, 52(7): 1882-1889.
13	Liu Q , Nayfeh M H , Yau S T . Brushed-on flexible supercapacitor sheets using a nanocomposite of polyaniline and carbon nanotubes[J]. J.Power. Sources, 2010, 195(21): 7480-7483.
14	Lv T , Yao Y , Li N , et al ．Wearable fiber-shaped energy conversion and storage devices based on aligned carbon nanotubes[J]. Nano Today, 2016, 11(5): 644-660.
15	Meng C Z , Liu C H , Chen L Z , et al . Highly flexible and all-solid-state paper-like polymer supercapacitors[J]. Nano Lett., 2010, 10(40): 25-4031.
16	李宁, 陈涛 . 石墨烯基电极材料在柔性全固态超级电容器中的研究进展[J]. 应用化学, 2018, 35(3): 259-271.
	Li N , Chen T . Recent progress on graphene-based flexible all-solid-state supercapacitors[J]. J. Chin. Appl. Chem., 2018, 35 (3): 259-271.
17	彭旭, 李典奇, 谢毅, 等 . 二维石墨烯和准二维类石墨烯在全固态柔性超级电容器中的应用[J]. 科学通报, 2013, 58(Z2): 2886-2894.
	Peng X , Li D Q , Xie Y , et al . Two-dimensional graphene/quasi-two-dimensional graphene analogues for flexible supercapacitor in all-solid-state[J]. Chin. Sci. Bull., 2013, 58(Z2): 2886-2894.
18	朱红艳, 赵建国, 庞明俊, 等 . 石墨烯/δ-MnO₂复合材料的制备及其超级电容器性能[J]. 化工学报, 2017, 68(12): 4824-4832.
	Zhu H Y , Zhao J G , Pang M J , et al . Preparation of graphene/δ-MnO₂ composites and supercapacitor performance[J]. CIESC Journal, 2017, 68(12): 4824-4832.
19	Cui Y , Chai J , Du H , et al . Facile and reliable in situ polymerization of poly(ethyl cyanoacrylate)-based polymer electrolytes toward flexible lithium batteries[J]. ACS Appl. Mater. Interfaces, 2017, 9(10): 8737-8741.
20	Cheng X , Jian P , Yang Z , et al . Gel polymer electrolytes for electrochemical energy storage[J]. Adv. Energy Mater., 2018, 8(7): 1702184.
21	Arya A , Sharma A L . Polymer electrolytes for lithium ion batteries: a critical study[J]. Ionics, 2017, 23(3): 497-540.
22	Dagousset L , Pognon G , Nguyen G T M , et al . Self-standing gel polymer electrolyte for improving supercapacitor thermal and electrochemical stability[J]. J. Power. Sources, 2018, 391(1): 86-93.
23	Wang Y , Xia Y . Recent progress in supercapacitors: from materials design to system construction[J]. Adv. Mater., 2013, 25(37): 5336-5342.
24	Hsu Y K , Chen Y C , Lin Y G , et al . High-cell-voltage supercapacitor of carbon nanotube/carbon cloth operating in neutral aqueous solution[J]. J. Mate. Chem., 2012, 22(8): 3383-3390.
25	Cui X , Lv R , Sagar R U R , et al . Reduced graphene oxide/carbon nanotube hybrid film as high performance negative electrode for supercapacitor[J]. Electrochimica Acta, 2015, 169: 342-350.
26	胡立鹃, 吴峰, 彭善枝, 等 . 生物质活性炭的制备及应用进展[J]. 化学通报, 2016, 79(3): 205-212.
	Hu L J , Wu F , Peng S Z , et al . Recent progress in preparation and utilization of biomass-based activated carbons[J]. Chem. Bull., 2016, 79(3): 205-212.
27	Goldfarb J L , Dou G , Salari M , et al . Biomass-based fuels and activated carbon electrode materials: an integrated approach to green energy systems[J]. ACS Sustain. Chem. Eng., 2017, 5(4): 3046-3054.
28	Gu X , Wang Y , Chao L , et al . Microporous bamboo biochar for lithium-sulfur batteries[J]. Nano Res., 2015, 8(1): 129-139.
29	Liu Y , Shi Z , Gao Y , et al . Biomass-swelling assisted synthesis of hierarchical porous carbon fibers for supercapacitor electrodes[J]. ACS Appl. Mater. Interfaces, 2016, 8(42): 28283-28290.
30	Hou J H , Cao C B , Ma J H , et al . Hierarchical porous nitrogen-doped carbon nanosheets derived from silk for ultrahigh-capacity battery anodes and supercapacitors[J]. ACS Nano, 2015, 9(3): 2556-2564.
31	Yu P F , Liang Y R , Liu Y L , et al . Rational synthesis of highly porous carbon from waste bagasse for advanced supercapacitor application[J]. ACS Sustain. Chem. Eng., 2018, 6(11): 15325-15332.
32	Fu P , Hu S , Sun L S , et al . Structural evolution of maize stalk particles during pyrolysis[J]. Bioresource Technol., 2009, 100(5): 4877-4883.
33	Jia M , Fang W , Xin J , et al . Metal ion-oxytetracycline interactions on maize straw biochar pyrolyzed at different temperatures[J]. Chem. Eng. J., 2016, 304(15): 934-940.
34	Yang G , Yun S Z , Min Q , et al . Chemical activation of carbon nano-onions for high-rate supercapacitor electrodes[J]. Carbon, 2013, 51: 52-58.
35	Wang J , Kaskel S . KOH activation of carbon-based materials for energy storage[J]. J. Mate. Chem., 2012, 22(45): 23710-23725.
36	Zhu H , Jia Z , Chen Y , et al . Tin anode for sodium-ion batteries using natural wood fiber as a mechanical buffer and electrolyte reservoir[J]. Nano Lett., 2013, 13(7): 3093-3100.
37	Liang Q H , Ye L , Huang Z H , et al . A honeycomb-like porous carbon derived from pomelo peel for use in high-performance supercapacitors[J]. Nanoscale, 2014, 6(22): 13831-13837.
38	Gong Y , Li D , Luo C , et al . Highly porous graphitic biomass carbon as advanced electrode materials for supercapacitors[J]. Green Chem., 2017, 17(19): 4132-4140.
39	Hao C , Liu D , Shen Z , et al . Functional biomass carbons with hierarchical porous structure for supercapacitor electrode materials[J]. Electrochimica Acta, 2015, 180: 241-251.
40	Qu J Y , Geng C , Lv S Y , et al . Nitrogen, oxygen and phosphorus decorated porous carbons derived from shrimp shells for supercapacitors[J]. Electrochimica Acta, 2015, 176: 982-988.
41	Gao S Y , Chen Y L , Fan H , et al . Large scale production of biomass-derived N-doped porous carbon spheres for oxygen reduction and supercapacitors[J]. J. Mater. Chem. A, 2014, 2(10): 3317-3324.
42	Xu H H , Hu X L , Sun Y M , et al . Flexible fiber-shaped supercapacitors based on hierarchically nanostructured composite electrodes[J]. Nano Research, 2015, 8(4): 1148-1158.
43	Chen S , Zhu J W , Wu X , et al . Graphene oxide-MnO₂nanocomposites for supercapacitors[J]. ACS Nano, 2010, 4(5): 6212-6218.
44	Tiruye G A , Muñoz-Torrero D , Thomas B , et al . Functional porous carbon nanospheres from sustainable precursors for high performance supercapacitors[J]. J.Mater. Chem. A, 2017, 5(31): 16263-16272.
45	Ma H Y , Li C , Zhang M , et al . Graphene oxide induced hydrothermal carbonization of egg proteins for high-performance supercapacitors[J]. J.
	Mate . Chem. A , 2017, 5(32): 17040-17047.
46	Wu C H , Deng S X , Wang H , et al . Preparation of novel three-dimensional NiO/ultrathin derived graphene hybrid for supercapacitor applications[J]. ACS Appl. Mate. Interfaces, 2014, 6(2): 1106-1112.

[1]	Xiaoxiong FAN, Lifang HAO, Chuigang FAN, Songgeng LI. Study on the catalytic denitrification performance of low-temperature NH₃-SCR over LaMnO₃/biochar catalyst [J]. CIESC Journal, 2023, 74(9): 3821-3830.
[2]	Jing LI, Conghao SHEN, Daliang GUO, Jing LI, Lizheng SHA, Xin TONG. Research progress in the application of lignin-based carbon fiber composite materials in energy storage components [J]. CIESC Journal, 2023, 74(6): 2322-2334.
[3]	Dong XU, Du TIAN, Long CHEN, Yu ZHANG, Qingliang YOU, Chenglong HU, Shaoyun CHEN, Jian CHEN. Preparation and electrochemical energy storage of polyaniline/manganese dioxide/polypyrrole composite nanospheres [J]. CIESC Journal, 2023, 74(3): 1379-1389.
[4]	Jiahao JIANG, Xiaole HUANG, Jiyun REN, Zhengrong ZHU, Lei DENG, Defu CHE. Qualitative and quantitative study on Pb²⁺ adsorption by biochar in solution [J]. CIESC Journal, 2023, 74(2): 830-842.
[5]	Jianxin CHEN, Ruijie ZHU, Nan SHENG, Chunyu ZHU, Zhonghao RAO. Preparation of cellulose-derived biomass porous carbon and its supercapacitor performance [J]. CIESC Journal, 2022, 73(9): 4194-4206.
[6]	Renjie GU, Jiawei ZHANG, Xueyang JIN, Lixiong WEN. Synthesis of nickel-cobalt hydroxide composites as supercapacitor materials by micro-impinging stream reactors and their performance study [J]. CIESC Journal, 2022, 73(8): 3749-3757.
[7]	Xue’an LIU, Liyi TANG, Jian QIN, Dajiang TANG, Zhangfa TONG, Huiying QU. Preparation of carbon nanotube bridged porous carbon by Ni/Co-ZIF-8 pyrolysis and its application to supercapacitors [J]. CIESC Journal, 2022, 73(7): 3287-3297.
[8]	Guanyi CHEN, Tujun TONG, Rui LI, Yanshan WANG, Beibei YAN, Ning LI, Li'an HOU. Influence of pyrolysis time on sludge-derived biochar performance for peroxymonosulfate activation [J]. CIESC Journal, 2022, 73(5): 2111-2119.
[9]	Xiqiang ZHAO, Jian ZHANG, Shuang SUN, Wenlong WANG, Yanpeng MAO, Jing SUN, Jinglong LIU, Zhanlong SONG. Study on the performance of biochar modified microspheres to remove inorganic phosphorus from chemical wastewater [J]. CIESC Journal, 2022, 73(5): 2158-2173.
[10]	Kun QIN, Jiale LI, Zhanghong WANG, Huiyan ZHANG. Biochars derived from Ca-rich mushroom residue for phosphorus-containing wastewater treatment [J]. CIESC Journal, 2022, 73(11): 5263-5274.
[11]	Tingting WANG, Xi ZENG, Zhennan HAN, Fang WANG, Peng WU, Guangwen XU. Reaction characteristics and kinetics of biomass char-steam gasification in micro-fluidized bed reaction analyzer [J]. CIESC Journal, 2022, 73(1): 294-307.
[12]	JIAO Shuai, YANG Lei, WU Tingting, LI Hongqiang, LYU Huihong, HE Xiaojun. Synthesis of nitrogen doped hierarchically porous carbon nanosheets for supercapacitor by mixed salt template [J]. CIESC Journal, 2021, 72(5): 2869-2877.
[13]	HUANG Zhongyi, SHI Liubin, FENG Yajun, LI Lishuo. Effect of ionic liquid pretreatment on eucalyptus char structure and its reactivity [J]. CIESC Journal, 2021, 72(4): 2267-2275.
[14]	Zhenzhen YE, Xinqi CHEN, Jian WANG, Bofan LI, Chaojie CUI, Gang ZHANG, Luming QIAN, Ying JIN, Weizhong QIAN. Evaluation of aging performance under high temperature of ionic liquid-based pouch supercapacitor [J]. CIESC Journal, 2021, 72(12): 6351-6360.
[15]	Yu WANG,Guangwei YU,Ruqing JIANG,Jiajia LIN,Yin WANG. Effect of particle size on phosphorus and heavy metals during the preparation of biochar from food waste biogas residue [J]. CIESC Journal, 2021, 72(10): 5344-5353.