Application of porous conductive gel PAM/CNTs-PEG in zinc-air batteries
-
摘要: 为实现锌-空气电池工业化生产,优化其空气扩散电极性能,使其有利于气体的扩散,并形成更多的三相界面。导电水凝胶是由导电材料和交联聚合物网络组成,聚合物网络提供支架,而导电材料赋予水凝胶良好的导电性。多孔的结构可以给气体更多的扩散通路,也有利于催化层的负载,形成更多的三相界面。本文采用聚丙烯酰胺基水凝胶,以聚乙二醇-2000 (PEG2000)为制孔剂,合成多孔聚丙烯酰胺/碳纳米管-聚乙二醇(PAM/CNTs-PEG)导电水凝胶。将制备的PAM/CNTs-PEG导电水凝胶浸泡于乙醇溶液中,可形成不同数量的介孔。本文研究了不同浸泡时间对于多孔PAM/CNTs-PEG导电水凝胶在柔性锌空电池中的性能影响。实验结果表明:乙醇浸泡5 h的导电凝胶电化学性能最好。当电压从1 mA/cm2 时的1.23 V到5 mA/cm2时的1.11 V,仅衰减了0.12 V。8.5 mA/cm2时产生最大功率密度为77.35 mW/cm2,且放电时具有1104.85 mA·h/g的高克容量,远高于其他导电凝胶。且有较好的导电性和应变灵敏度,可应用于传感等领域。Abstract: In order to realize the industrial production of zinc-air battery, the performance of its air diffusion electrode is optimized to make it conducive to the diffusion of gas and to form more three-phase interfaces. The conductive hydrogel is composed of a conductive material and a cross-linked polymer network, the polymer network provides the scaffold, and the conductive material gives the hydrogel good electrical conductivity. The porous structure can give more diffusion paths to the gas, and is also conducive to the load of the catalytic layer, forming more three-phase interfaces. In this paper, polyacrylamide hydrogel was used to synthesize porous polyacrylamide/carbon nanotubes-polyethylene glycol (PAM/CNTs-PEG) conductive hydrogel with polyethylene glycol 2000 (PEG2000) as pore-making agent. The prepared PAM/CNTs-PEG conductive hydrogels were immersed in ethanol solution to form different numbers of mesopores. The effect of different immersion time on the properties of porous PAM/CNTs-PEG conductive hydrogels in flexible zinc-air cells was studied. The experimental results show that the electrochemistry performance of the conductive gel soaked in ethanol for 5 h is the best. When the voltage changes from 1.23 V at 1 mA/cm2 to 1.11 V at 5 mA/cm2, the attenuation is only 0.12 V. The maximum power density is 77.35 mW/cm2 at 8.5 mA/cm2, and the high gram capacity of 1104.85 mA·h/g at discharge is much higher than that of other conductive gels. It has good electrical conductivity and strain sensitivity and can be used in sensing and other fields.
-
Key words:
- zinc-air battery /
- electrical conductive gel /
- polyacrylamide /
- polyethylene glycol /
- hole making agent
-
表 1 未加PEG及加入PEG不同乙醇浸泡时间的PAM/CNTs-PEG导电水凝胶的孔隙率
Table 1. Porosity of PAM/CNTs-PEG conducting hydrogels without PEG and with PEG in different ethanol soaking time
Sample Pore volume/
(mL·g−1)Density ρ/(g·cm−3) Porosity/% Unadded 0.0070 1.2129 3.96 1 h 0.0065 1.3217 6.50 2 h 0.0374 1.2364 27.35 5 h 0.2194 1.0754 65.71 10 h 4.7320 1.0206 95.89 -
[1] GÖHLERT T, SILES P F, PÄSSLER T, et al. Ultra-thin all-solid-state micro-supercapacitors with exceptional performance and device flexibility[J]. Nano Energy,2017,33:387-392. doi: 10.1016/j.nanoen.2017.01.054 [2] ZHU T, NI Y, BIESOLD G M, et al. Recent advances in conductive hydrogels: Classifications, properties, and applications[J]. Chemical Society Reviews,2023,52(2):473-509. doi: 10.1039/D2CS00173J [3] SONG Y, NIU L, MA P, et al. Rapid preparation of anti-freezing conductive hydrogels for flexible strain sensors and supercapacitors[J]. ACS Applied Materials & Interfaces,2023,15(7):10006-10017. [4] NISHIDE H, OYAIZU K. Toward flexible batteries[J]. Science,2008,319(5864):737-738. doi: 10.1126/science.1151831 [5] WANG J, WU H, GAO D, et al. High-density iron nanoparticles encapsulated within nitrogen-doped carbon nanoshell as efficient oxygen electrocatalyst for zinc-air battery[J]. Nano Energy,2015,13:387-396. doi: 10.1016/j.nanoen.2015.02.025 [6] HAN X, WU X, ZHONG C, et al. NiCo2S4 nanocrystals anchored on nitrogen-doped carbon nanotubes as a highly efficient bifunctional electrocatalyst for rechargeable zinc-air batteries[J]. Nano Energy,2017,31:541-550. doi: 10.1016/j.nanoen.2016.12.008 [7] FU J, CANO Z P, PARK M G, et al. Electrically rechargeable zinc-air batteries: Progress, challenges, and perspectives[J]. Advanced Materials,2017,29(7):1604685. doi: 10.1002/adma.201604685 [8] YOO H D, MARKEVICH E, SALITRA G, et al. On the challenge of developing advanced technologies for electrochemical energy storage and conversion[J]. Materials Today,2014,17(3):110-121. doi: 10.1016/j.mattod.2014.02.014 [9] AASEN D, CLARK M, IVEY D G. A gas diffusion layer impregnated with Mn3O4-decorated N-doped carbon nanotubes for the oxygen reduction reaction in zinc-air batteries[J]. Batteries & Supercaps,2019,2(10):882-893. [10] WANG R, CHEN Z, HU N, et al. Nanocarbon-based electrocatalysts for rechargeable aqueous Li/Zn-air batteries[J]. ChemElectroChem,2018,5(14):1745-1763. doi: 10.1002/celc.201800141 [11] ZHU Y, LIN L, CHEN Y, et al. Extreme temperature-tolerant conductive gel with antibacterial activity for flexible dual-response sensors[J]. ACS Applied Materials & Interfaces,2020,12(50):56470-56479. [12] WEI J, XIAO P, CHEN T. Water-resistant conductive gels toward underwater wearable sensing[J]. Advanced Materials, 2023, 35(42): 2211758. [13] CHEN L, ZHANG W, DONG Y, et al. Polyaniline/poly(acrylamide-co-sodium acrylate) porous conductive hydrogels with high stretchability by freeze-thaw-shrink treatment for flexible electrodes[J]. Macromolecular Materials and Engineering,2020,305(3):1900737. doi: 10.1002/mame.201900737 [14] WANG S, GUAN S, ZHU Z, et al. Hyaluronic acid doped-poly(3, 4-ethylenedioxythiophene)/chitosan/gelatin (PEDOT-HA/Cs/Gel) porous conductive scaffold for nerve regeneration[J]. Materials Science and Engineering: C,2017,71:308-316. doi: 10.1016/j.msec.2016.10.029 [15] LI Z H, LIU W T, LI Z Y, et al. Swelling and thermal properties of porous PNIPAM/PEG hydrogels prepared by radiation polymerization[J]. Nuclear Science and Techniques,2013,24(2):17-24. [16] 李健昱, 徐朝阳, 周欢, 等. 多孔PVA/CNFs复合水凝胶的制备与性能[J]. 包装工程, 2016, 37(15):56-60. doi: 10.19554/j.cnki.1001-3563.2016.15.012LI Jianyu, XU Chaoyang, ZHOU Huan, et al. Preparation and properties of porous PVA/CNFs composite hydrogel[J]. Packaging Engineering,2016,37(15):56-60(in Chinese). doi: 10.19554/j.cnki.1001-3563.2016.15.012 [17] 张思雨. 基于MXene导电水凝胶的制备及性能研究[D]. 西宁: 青海师范大学, 2022.ZHANG Siyu. Preparation and properties of conductive hydrogel based on MXene [D]. Xining: Qinghai Normal University, 2022(in Chinese). [18] SHI Y, YU G H. Designing hierarchically nanostructured conductive polymer gels for electrochemical energy storage and conversion[J]. Chemistry of Materials,2016,28(8):2466-2477. doi: 10.1021/acs.chemmater.5b04879 [19] 石奋玲, 杜莹, 逯帅帅, 等. 基于甜菜碱的两性离子导电水凝胶的合成及性能[J]. 印染, 2023, 49(1):49-52.SHI Fenling, DU Ying, LU Shuaishuai, et al. Synthesis and properties of zwitterionic conductive hydrogel based on betaine[J]. Dyeing and Finishing,2023,49(1):49-52(in Chinese). [20] 汪锋. 可拉伸导电水凝胶设计及其制备方法与储能器件应用研究[D]. 南京: 南京邮电大学, 2022.WANG Feng. Design and preparation of stretchable conductive hydrogel and its application to energy storage devices[D]. Nanjing: Nanjing University of Posts and Telecommunications, 2022(in Chinese). [21] 魏垂高, 周丽娜, 张宇彪, 等. 基于导电水凝胶的柔性电子皮肤传感器研究[J]. 电子元件与材料, 2022, 41(11):1149-1157. doi: 10.14106/j.cnki.1001-2028.2022.0609WEI Chuigao, ZHOU Lina, ZHANG Yubiao, et al. Research on flexible electronic skin sensor based on conductive hydrogel[J]. Electronic Components & Materials,2022,41(11):1149-1157(in Chinese). doi: 10.14106/j.cnki.1001-2028.2022.0609 [22] 李媛. 基于中性凝胶聚合物电解质的柔性锌空气电池研究[D]. 天津: 天津大学, 2019.LI Yuan. Research on flexible zinc-air battery based on neutral gel polymer electrolyte[D]. Tianjin: Tianjin University, 2019(in Chinese). [23] 程时富. 多孔炭材料的制备及其电化学性能[D]. 上海: 华东师范大学, 2020.CHENG Shifu. Preparation and electrochemical properties of porous carbon materials[D]. Shanghai: East China Normal University, 2020(in Chinese). [24] 陈东方, 裴普成, 宋鑫, 等. 锌空燃料电池电化学阻抗等效电路模型[J]. 清华大学学报(自然科学版), 2020, 60(2):139-146. doi: 10.16511/j.cnki.qhdxxb.2019.22.042CHEN Dongfang, PEI Pucheng, SONG Xin, et al. Electrochemical impedance equivalent circuit model for zinc-air fuel cells[J]. Journal of Tsinghua University (Science and Technology),2020,60(2):139-146(in Chinese). doi: 10.16511/j.cnki.qhdxxb.2019.22.042 [25] MA M, SHANG Y, SHEN H, et al. Highly transparent conductive ionohydrogel for all-climate wireless human-motion sensor[J]. Chemical Engineering Journal,2021,420:129865. doi: 10.1016/j.cej.2021.129865