通过控制水热反应原料中氧化石墨与氯化锰的比例、甲醇的添加量以及水热反应的温度,制备了不同反应条件下的RGO/MnOx复合材料.利用 X射线衍射(XRD)、X 射线光电子能谱(XPS)和场发射扫描电镜(FE-SEM)表征了样品的晶相结构、氧化石墨的不同含氧基团含量、锰的不同化学价态及其比例和微观形貌.利用电化学工作站测试了样品在三电极测试系统下的循环伏安曲线(cyclic voltammetry,CV)、计时电位曲线(chronopotentiometry)和交流阻抗图谱(electrochemical impedance spectroscopy,EIS).电化学测试表明,用1 mol/L Na2 SO4作为电解液,电位范围为0~1 V,充放电电流密度为1 A/g 的条件下,样品的最佳比电容高达289.8 F/g,在充放电电流密度为20 A/g的条件下,比电容仍然有223.9 F/g,并且在充放电密度为5 A/g的的条件下充放电循环1000次后样品的比电容仍然保持在初始比电容的84.5%.
In the present work RGO/MnOx composites were fabracated by a hydrothermal method at different conditions.The crystal structure,chemical state of the elements,and the microstrucuture of the as-obtained samples were chracterized using power X-ray diffraction (XRD),X-ray photoelectron spectroscopy (XPS)and field emission scanning electron microscopy (FESEM).Moreover,the electrochemical behaviors were evaluated by cyclic voltammogram (CV),galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS)in a three electrod system.The test results showed that the specific capacitance of the optimal sample was calculated to be 289.8 F/g in 1 mol/L Na2 SO4 electroyte at a current density of 1 A/g with a operating window from 0 to 1 V,and its specific capacitance was 223.9 F/g even at a current rate density of 20 A/g.In addition, the capacitance retention ratio of the sample remained 88% after 1 000 cycles at a high current density of 5 A/g.
参考文献
[1] | Chemical Reviews Group .What Are Batteries,Fuel Cells,and Supercapacitors?[J].Chemical Reviews,2004(10):4245-4269. |
[2] | PATRICE SIMON;YURY GOGOTSI .Materials for electrochemical capacitors[J].Nature materials,2008(11):845-854. |
[3] | Yanwu Zhu;Shanthi Murali;Meryl D. Stoller;K. J. Ganesh;Weiwei Cai;Paulo J. Ferreira;Adam Pirkle;Robert M. Wallace;Katie A. Cychosz;Matthias Thommes;Dong Su;Eric A. Stach;Rodney S. Ruoff .Carbon-Based Supercapacitors Produced by Activation of Graphene[J].Science,2011(Jun.24 TN.6037):1537-1541. |
[4] | Guoping Wang;Lei Zhang;Jiujun Zhang .A review of electrode materials for electrochemical supercapacitors[J].Chemical Society Reviews,2012(2):797-828. |
[5] | Yan J;Wang Q;Wei T et al.Recent advances in design and fabrication of electrochemical supercapacitors with high energy densities[J].Adv Energy Mater,2014(4):1300816(1-130081643. |
[6] | Dong B;Zhang X;Xu X et al.Preparation of scale-like nickel cobaltite nanosheets assembled on nitrogen-doped reduced graphene oxide for high-performance supercapaci-tors[J].CARBON,2014,80:222-228. |
[7] | Xu X;Zhou H;Ding S et al.The facile synthesis of hi-erarchical NiCoO2 nanotubes comprised ultrathin nanosheets for supercapacitors[J].Journal of Power Sources,2014,267:641-647. |
[8] | Liang J;Fan Z;Chen S et al.Hierarchical NiCo2 O4 nanosheets@halloysite nanotubes with ultrahigh capaci-tance and long cycle stability as electrochemical pseudoca-pacitor materials[J].CHEMISTRY OF MATERIALS,2014,26(15):4354-4360. |
[9] | 张子瑜,胡中爱,杨玉英,王欢文,常艳琴,陈艳丽,雷自强.Ce掺杂Mn3O4及其电化学电容行为[J].物理化学学报,2011(07):1673-1678. |
[10] | Shengtao Xing;Zicheng Zhou;Zichuan Ma;Yinsu Wu .Facile synthesis and electrochemical properties of Mn_3O_4 nanoparticles with a large surface area[J].Materials Letters,2011(3):517-519. |
[11] | Deepak P. Dubai;Rudolf Holze .All-solid-state flexible thin film supercapacitor based on Mn_3O_4 stacked nanosheets with gel electrolyte[J].Energy,2013(Mar.):407-412. |
[12] | Pang S.C.;Anderson M.A. .Novel Electrode Materials for Thin-Film Ultracapacitors: Comparison of Electrochemical Properties of Sol-Gel-Derived and Electrodeposited Manganese Dioxide[J].Journal of the Electrochemical Society,2000(2):444-450. |
[13] | Li Li Zhang;Tianxin Wei;Wenjuan Wang .Manganese oxide-carbon composite as supercapacitor electrode materials[J].Microporous and mesoporous materials: The offical journal of the International Zeolite Association,2009(1/3):260-267. |
[14] | Yu, G.;Xie, X.;Pan, L.;Bao, Z.;Cui, Y. .Hybrid nanostructured materials for high-performance electrochemical capacitors[J].Nano Energy,2013(2):213-234. |
[15] | Weifeng Wei;Xinwei Cui;Weixing Chen .Manganese oxide-based materials as electrochemical supercapacitor electrodes[J].Chemical Society Reviews,2011(3):1697-1721. |
[16] | Yan Wang;Zhiqiang Shi;Yi Huang .Supercapacitor Devices Based on Graphene Materials[J].The journal of physical chemistry, C. Nanomaterials and interfaces,2009(30):13103-13107. |
[17] | Liu, C.;Yu, Z.;Neff, D.;Zhamu, A.;Jang, B.Z. .Graphene-based supercapacitor with an ultrahigh energy density[J].Nano letters,2010(12):4863-4868. |
[18] | Stoller MD;Park SJ;Zhu YW;An JH;Ruoff RS .Graphene-Based Ultracapacitors[J].Nano letters,2008(10):3498-3502. |
[19] | Wu, Z.-S.;Ren, W.;Wang, D.-W.;Li, F.;Liu, B.;Cheng, H.-M. .High-energy MnO_2 nanowire/graphene and graphene asymmetric electrochemical capacitors[J].ACS nano,2010(10):5835-5842. |
[20] | Qian Cheng;Jie Tang;Jun Ma .Graphene and nanostructured MnO2 composite electrodes for supercapacitors[J].Carbon: An International Journal Sponsored by the American Carbon Society,2011(9):2917-2925. |
[21] | Jeong Woo Lee;Anthony S. Hall;Jong-Duk Kim .A Facile and Template-Free Hydrothermal Synthesis of Mn3O4 Nanorods on Graphene Sheets for Supercapacitor Electrodes with Long Cycle Stability[J].Chemistry of Materials: A Publication of the American Chemistry Society,2012(6):1158-1164. |
[22] | Ambrosi A;Chua C K;Bonanni A et al.Electrochemis-try of graphene and related materials[J].CHEMICAL REVIEWS,2014,114(14):7150-7188. |
[23] | Staaf L G H;Lundgren P;Enoksson P .Present and fu-ture supercapacitor carbon electrode materials for im-proved energy storage used in intelligent wireless sensor systems[J].Nano Energy,2014,9:128-141. |
[24] | 李乐,贺蕴秋,储晓菲,李一鸣,孙芳芳,黄河洲.水热合成部分还原氧化石墨烯-K2Mn4O8超级电容器纳米复合材料[J].物理化学学报,2013(08):1681-1690. |
[25] | Hummers W S;Offeman R E .Preparation of graphitic oxide[J].Journal of the American Chemical Society,1958,80(6):1339-1339. |
[26] | Sasha Stankovich;Dmitriy A. Dikin;Richard D. Piner .Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide[J].Carbon: An International Journal Sponsored by the American Carbon Society,2007(7):1558-1565. |
[27] | Hyeon-Jin Shin;Ki Kang Kim;Anass Benayad;Seon-Mi Yoon;Hyeon Ki Park;In-Sun Jung;Mei Hua Jin;Hae-Kyung Jeong;Jong Min Kim;Jae-Young Choi;Young Hee Lee .Efficient Reduction of Graphite Oxide by Sodium Borohydride and Its Effect on Electrical Conductance[J].Advanced functional materials,2009(12):1949-1961. |
[28] | Nesbitt H W;Banerjee D .Interpretation of XPS Mn(2p)spectra of Mn oxyhydroxides and constraints on the mechanism of MnO2 precipitation[J].American Mineralogist,1998,83(3-4):305-315. |
[29] | Biesinger M C;Payne B P;Grosvenor A P et al.Resol-ving surface chemical states in XPS analysis of first row transition metals,oxides and hydroxides:Cr,Mn,Fe,Co and Ni[J].Applied Surface Sinence,2011,257(7):2717-2730. |
[30] | Devaraj S;Munichandraiah N .Effect of crystallographic structure of MnO2 on its electrochemical capacitance properties[J].The journal of physical chemistry, C. Nanomaterials and interfaces,2008(11):4406-4417. |
[31] | Hu CC;Wu YT;Chang KH .Low-temperature hydrothermal synthesis of Mn3O4 and MnOOH single crystals: Determinant influence of oxidants[J].Chemistry of Materials: A Publication of the American Chemistry Society,2008(9):2890-2894. |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%