• P-ISSN 0974-6846 E-ISSN 0974-5645

Indian Journal of Science and Technology


Indian Journal of Science and Technology

Year: 2021, Volume: 14, Issue: 7, Pages: 676-689

Original Article

Surfactant assisted morphological transformation of rod-like ZnCo2O4 into hexagonal-like structures for high-performance supercapacitors

Received Date:05 November 2020, Accepted Date:04 February 2021, Published Date:08 February 2021


Objectives: To develop the microstructures of rod-shaped ZnCo2O4 (ZCOUrea) and hexagonal-shaped ZnCo2O4 (ZCO-NH4F) through the change of surfactants such as urea and NH4F in the reaction and to investigate the physicochemical and electrochemical properties for high-performance supercapacitors. Methods: The structural and morphological characteristics of two prepared samples were analyzed through X-ray diffraction analysis (XRD), Scanning electron microscope (SEM) analysis, and Transmission electron microscope (TEM) analysis, respectively. The electrochemical performance was evaluated using Cyclic voltammetry (CV), Galvanostatic charge-discharge (GCD), and Electrochemical impedance spectroscopy (EIS) analysis. Findings: The crystalline nature and phase purity of the as prepared samples were confirmed from XRD, and the structural parameters such as lattice parameter (a), microstrain (e ), dislocation density (d ), cell volume (v), and average crystalline size (D) for both the samples were determined. The SEM and TEM analysis revealed morphological characteristics of the samples. The electrochemical analysis of ZCO-Urea and ZCO-NH4F electrodes were tested for supercapacitor application in 1M of aqueous KOH electrolyte and exhibit an areal capacitance of 31 mF cm-2, and 41.43 mF cm-2, respectively, obtained at a current density of 10 mA cm-2. And also showed outstanding cyclic stability over 1000 charge-discharge cycles. Applications: The simple and inexpensive method of synthesized surfactant-assisted morphological transformation of ZCO microstructures will introduce new directions in this emerging energy field.

Keywords: ZnCo2O4; Urea; NH4F; areal capacitance; supercapacitors


  1. Sun A, Xie L, Wang D, Wu Z. Enhanced energy storage performance from Co-decorated MoS2 nanosheets as supercapacitor electrode materials. Ceramic International. 2018;44:13434–13438. Available from: https://doi.org/10.1016/j.ceramint.2018.04.113
  2. Kulkarni P, Nataraj SK, Balakrishna RG, Nagaraju DH, Reddy M. Nanostructured binary and ternary metal sulfides: synthesis methods and their application in energy conversion and storage devices. J. Mater. Chem. A. 2017;5(42):22040–22094. Available from: https://dx.doi.org/10.1039/c7ta07329a
  3. Yi TF, Li Y, Li YM, Luo S, Liu YG. ZnS nanoparticles as the electrode materials for high-performance supercapacitors. Solid State Ionics. 2019. Available from: https://doi.org/10.1016/j.ssi.2019.115074
  4. Reddy BJ, Vickraman P, Justin AS. A facile synthesis of novel a-ZnMoO4 microspheres as electrode material for supercapacitor applications. Bulletin of Materials Science. 2019;42:1–6. Available from: https://doi.org/10.1007/s12034-019-1749-9
  5. Kazemi SH, Tabibpour M, Kiani MA, Kazemi H. An advanced asymmetric supercapacitor based on a binder-free electrode fabricated from ultrathin CoMoO4 nano-dandelions. RSC Advances. 2016;6(75):71156–71164. Available from: https://dx.doi.org/10.1039/c6ra05703a
  6. Xu K, Chao J, Li W, Liu Q, Wang Z, Liu X, et al. CoMoO4•0.9H2O nanorods grown on reduced graphene oxide as advanced electrochemical pseudocapacitor materials. RSC Advances. 2014;4:34307–34314. Available from: https://doi.org/10.1039/c4ra04827j
  7. Mandal M, Ghosh D, Giri S, Shakir I, Das CK. Polyaniline-wrapped 1D CoMoO4•0.75H2O nanorods as electrode materials for supercapacitor energy storage applications. RSC Advances. 2014;p. 30832–30839. Available from: https://doi.org/10.1039/c4ra03399j
  8. Candler J, Elmore T, Gupta BK, Dong L, Palchoudhury S, Gupta RK. New insight into high-temperature driven morphology reliant CoMoO4 flexible supercapacitors. New Journal of Chemistry. 2015;39(8):6108–6116. Available from: https://dx.doi.org/10.1039/c5nj00446b
  9. Zhu J, Xiang L, Xi D, Zhou Y, Yang J. One-step hydrothermal synthesis of flower-like CoS hierarchitectures for application in supercapacitors. Bulletin of Materials Science. 2018;41(2). Available from: https://dx.doi.org/10.1007/s12034-018-1570-x
  10. Pan Y, Gao H, Zhang M, Li L, Wang Z. Facile synthesis of ZnCo2O4micro-flowers and micro-sheets on Ni foam for pseudocapacitor electrodes. Journal of Alloys and Compounds. 2017;702:381–387. Available from: https://doi.org/10.1016/j.jallcom.2017.01.136
  11. Cheng M, Fan H, Song Y, Cui Y, Wang R. Interconnected hierarchical NiCo2O4 microspheres as high-performance electrode materials for supercapacitors. Dalton Transactions. 2017;46:9201–9209. Available from: https://doi.org/10.1039/c7dt01289f
  12. Guan B, Guo D, Hu L, Zhang G, Fu T, Ren W, et al. Facile synthesis of ZnCo2O4 nanowire cluster arrays on Ni foam for high-performance asymmetric supercapacitors. J. Mater. Chem. A. 2014;2(38):16116–16123. Available from: https://dx.doi.org/10.1039/c4ta02378a
  13. Ensafi AA, Moosavifard SE, Rezaei B, Kaverlavani SK. Engineering onion-like nanoporous CuCo2O4 hollow spheres derived from bimetal–organic frameworks for high-performance asymmetric supercapacitors. Journal of Materials Chemistry A. 2018;6(22):10497–10506. Available from: https://dx.doi.org/10.1039/c8ta02819b
  14. Rajesh JA, Min BK, Kim JH, Kim H, Ahn KS. Cubic Spinel AB2O 4 Type Porous ZnCo2O4 Microspheres: Facile Hydrothermal Synthesis and Their Electrochemical Performances in Pseudocapacitor. Journal of The Electrochemical Society. 2016;163. Available from: https://doi.org/10.1149/2.0071613jes
  15. Rajesh JA, Min BK, Kim JH, Kang SH, Kim H, Ahn KS. Facile hydrothermal synthesis and electrochemical supercapacitor performance of hierarchical coral-like ZnCo2O4 nanowires. Journal of Electroanalytical Chemistry. 2017;785:48–57. Available from: https://doi.org/10.1016/j.jelechem.2016.12.027
  16. Kathalingam A, Ramesh S, Yadav HM, Choi JH, Kim HS, Kim HS. Nanosheet-like ZnCo2O4@nitrogen doped graphene oxide/polyaniline composite for supercapacitor application: Effect of polyaniline incorporation. Journal of Alloys and Compounds. 2020;830. Available from: https://dx.doi.org/10.1016/j.jallcom.2020.154734
  17. Yu H, Zhao H, Wu Y, Chen B, Sun J. Electrospun ZnCo2O4/C composite nanofibers with superior electrochemical performance for supercapacitor. Journal of Physics and Chemistry of Solids. 2020;140. Available from: https://doi.org/10.1016/j.jpcs.2020.109385
  18. Reddy GR, Dillip GR, Sreekanth TVM, Rajavaram R, Raju BDP, Nagajyothi PC, et al. In situ engineered 0D interconnected network-like CNS decorated on Co-rich ZnCo2O4 2D nanosheets for high-performance supercapacitors. Journal of the Taiwan Institute of Chemical Engineers. 2020;113:155–164. Available from: https://dx.doi.org/10.1016/j.jtice.2020.08.002
  19. Reddy GR, Kumar NS, Raju BDP, Shanmugam G, Al-Ghurabi EH, Asif M. Enhanced Supercapacitive Performance of Higher-Ordered 3D-Hierarchical Structures of Hydrothermally Obtained ZnCo2O4 for Energy Storage Devices. Nanomaterials. 2020;10(6). Available from: https://dx.doi.org/10.3390/nano10061206
  20. Gund GS, Dubal DP, Dhawale DS, Shinde SS, Lokhande CD. Porous CuO nanosheet clusters prepared by a surfactant assisted hydrothermal method for high performance supercapacitors. RSC Advances. 2013;3(46). Available from: https://dx.doi.org/10.1039/c3ra43254h
  21. Han X, Liao F, Zhang Y, Han X, Xu C, Chen H. Solvothermal preparation of zinc cobaltite mesoporous microspheres for high-performance electrochemical supercapacitors. Journal of Alloys and Compounds. 2019;781:425–432. Available from: https://doi.org/10.1016/j.jallcom.2018.12.079
  22. Lahure P, Salunke P, Soliwal R, Yadav A, Tripathi S, Koser AA. X-Ray Diffraction Study of ZnO Nanoparticles. International Journal of Scientific Researh in Physics and Applied Sciences. 2015;3:32–33. Available from: https://www.isroset.org/pub_paper/ijsrpas/isroset-nsrtnp-2014-0008.pdf
  23. Priya M, Premkumar VK, Vasantharani P, Sivakumar G. Structural and electrochemical properties of ZnCo2O4 nanoparticles synthesized by hydrothermal method. Vacuum. 2019;167:307–312. Available from: https://dx.doi.org/10.1016/j.vacuum.2019.06.020
  24. Kianpour G, Salavati-Niasari M, Emadi H. Precipitation synthesis and characterization of cobalt molybdates nanostructures. Superlattices and Microstructures. 2013;58:120–129. Available from: https://dx.doi.org/10.1016/j.spmi.2013.01.014
  25. Liu MC, Kong L, Kang L, Li X, Walsh FC, Xing M, et al. Synthesis and characterization of M3V2O8 (M = Ni or Co) based nanostructures: A new family of high performance pseudocapacitive materials. Journal of Materials Chemistry A. 2014;2:4919–4926. Available from: https://doi.org/10.1039/c4ta00582a
  26. Shang Y, Xie T, Gai Y, Su L, Gong L, Lv H. Electrochimica Acta Self-assembled hierarchical peony-like ZnCo2O4 for high-performance asymmetric supercapacitors. Electrochimica Acta. 2017;253:281–290. Available from: https://doi.org/10.1016/j.electacta.2017.09.042
  27. Mary AJC, Bose AC. Surfactant assisted ZnCo2O4 nanomaterial for supercapacitor application. Applied Surface Science. 2018;449:105–112. Available from: https://dx.doi.org/10.1016/j.apsusc.2018.01.117
  28. Venkatachalam V, Alsalme A, Alghamdi A, Jayavel R. Hexagonal-like NiCo2O4 nanostructure based high-performance supercapacitor electrodes. Ionics. 2017;23(4):977–984. Available from: https://dx.doi.org/10.1007/s11581-016-1868-x
  29. Bhagwan J, Nagaraju G, Ramulu B, Yu JS. Promotive Effect of MWCNT on ZnCo2O4Hexagonal Plates and Their Application in Aqueous Asymmetric Supercapacitor. Journal of The Electrochemical Society. 2019;166(2):A217–A224. Available from: https://dx.doi.org/10.1149/2.0631902jes
  30. Xiao X, Wang G, Zhang M, Wang Z, Zhao R, Wang Y. Electrochemical performance of mesoporous ZnCo2O4 nanosheets as an electrode material for supercapacitor. Ionics (Kiel). 2018;24:2435–2443. Available from: https://doi.org/10.1007/s11581-017-2354-9
  31. Dixit SG, Mahadeshwar AR, Haram SK. Some aspects of the role of surfactants in the formation of nanoparticles. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 1998;133(1-2):69–75. Available from: https://dx.doi.org/10.1016/s0927-7757(97)00126-x
  32. Morsy SMI. Role of surfactants in nanotechnology and their applications. International Journal of Current Microbiology and Applied Sciences. 2014;3:237–260. Available from: https://www.ijcmas.com/vol-3-5/salwa%20m.i.%20morsy.pdf
  33. Hu MZC, Harris MT, Byers CH. Nucleation and growth for synthesis of nanometric zirconia particles by forced hydrolysis. Journal of Colloid and Interface Sciences. 0198;198:87–99. Available from: https://doi.org/10.1006/jcis.1997.5290
  34. Kakiuchi K, Hosono E, Kimura T, Imai H, Fujihara S. Fabrication of mesoporous ZnO nanosheets from precursor templates grown in aqueous solutions. Journal of Sol-Gel Science and Technology. 2006;39(1):63–72. Available from: https://dx.doi.org/10.1007/s10971-006-6321-6
  35. Marinho JZ, Romeiro FC, Lemos SCS, Motta FV, Riccardi CS, Li MS, et al. Urea-Based Synthesis of Zinc Oxide Nanostructures at Low Temperature. Journal of Nanomaterials. 2012;2012:1–7. Available from: https://dx.doi.org/10.1155/2012/427172
  36. Caullet P, Paillaud JL, Simon-Masseron A, Soulard M, Patarin J. The fluoride route: a strategy to crystalline porous materials. Comptes Rendus Chimie. 2005;8(3-4):245–266. Available from: https://dx.doi.org/10.1016/j.crci.2005.02.001
  37. Chen G, Jiang L, Wang L, Zhang J. Synthesis of mesoporous ZSM-5 by one-pot method in the presence of polyethylene glycol. Microporous and Mesoporous Materials. 2010;134:189–194. Available from: https://doi.org/10.1016/j.micromeso.2010.05.025
  38. Du H, Wang Y, Yuan H, Jiao L. Facile Synthesis and High Capacitive Performance of 3D Hierarchical Ni(OH)2 Microspheres. Electrochimca Acta. 0196;196:84–91. Available from: https://doi.org/10.1016/j.electacta.2016.02.190
  39. Wu X, Han X, Ma X, Zhang W, Deng Y, Zhong C, et al. Morphology-Controllable Synthesis of Zn-Co-Mixed Sulfide Nanostructures on Carbon Fiber Paper Toward Efficient Rechargeable Zinc-Air Batteries and Water Electrolysis. ACS Applied Materials and Interfaces. 2017;9:12574–12583. Available from: https://doi.org/10.1021/acsami.6b16602
  40. Wang Z, Lu Y, Yuan S, Shi L, Zhao Y, Zhang M, et al. Hydrothermal synthesis and humidity sensing properties of size-controlled Zirconium Oxide (ZrO2) nanorods. Journal of Colloid and Interface Sciences. 2013;396:9–15. Available from: https://doi.org/10.1016/j.jcis.2012.12.068
  41. Wu C, Cai J, Zhang Q, Zhou X, Zhu Y, Li L, et al. Direct growth of urchin-like ZnCo2O4 microspheres assembled from nanowires on nickel foam as high-performance electrodes for supercapacitors. Electrochimica Acta. 2015;169:202–209. Available from: https://doi.org/10.1016/j.electacta.2015.04.079
  42. Gutturu RR, STVM, Rajavaram R, Borelli DPR, Dillip GR, Nagajyothi PC, et al. Effect of reaction time and PVP contents on morphologies of hierarchical 3D flower-like ZnCo2O4 microstructures for energy storage devices. International Journal of Energy Research. 2020;p. 1–15. Available from: https://doi.org/10.1002/er.5719
  43. Cheng J, Lu Y, Qiu K, Yan H, Hou X, Xu J, et al. Mesoporous ZnCo2O4 nanoflakes grown on nickel foam as electrodes for high performance supercapacitors. Physical Chemistry and Chemical Physics. 2015;17:17016–17022. Available from: https://doi.org/10.1039/c5cp01629k
  44. Prasad K, Reddy GR, Rajesh M, Babu PR, Shanmugam G, Sushma NJ, et al. Electrochemical Performance of 2D-Hierarchical sheet-like ZnCo2O4 Microstructures for Supercapacitor Applications. Crystals. 2020;10:1–13. Available from: https://doi.org/10.3390/cryst10070566
  45. Wang X, Li W, Wang X, Zhang J, Sun L, Gao C, et al. Electrochemical properties of NiCoO2 synthesized by hydrothermal method. RSC Advances. 2017;7:50753–50759. Available from: https://doi.org/10.1039/c7ra10232a
  46. Lu J, Ran H, Li J, Wan J, Wang C, Ji P, et al. A fast composite-hydroxide-mediated approach for synthesis of 2D-LiCoO2 for high performance asymmetric supercapacitor. Electrochimica Acta. 2020;331. Available from: https://doi.org/10.1016/j.electacta.2019.135426
  47. Liu Y, Wang N, Yang C, Hu W. Sol-gel synthesis of nanoporous NiCo2O4 thin films on ITO glass as high-performance supercapacitor electrodes. Ceramics International. 2016;42:11411–11416. Available from: https://doi.org/10.1016/j.ceramint.2016.04.071
  48. Soram BS, Dai J, Kshetri T, Kim NH, Lee JH. Vertically grown and intertwined Co(OH)2 nanosheet@Ni-mesh network for transparent flexible supercapacitor. Chemical Engineering Journal. 2020;391. Available from: https://dx.doi.org/10.1016/j.cej.2019.123540
  49. Zhang J, Wang Y, Wu J, Shu X, Yu C, Cui J, et al. Remarkable supercapacitive performance of TiO2 nanotube arrays by introduction of oxygen vacancies. Chemical Engineering Journal. 2017;313:1071–1081. Available from: https://doi.org/10.1016/j.cej.2016.11.004
  50. Liu XY, Zhang YQ, Xia XH, Shi SJ, Lu Y, Wang XL, et al. Self-assembled porous NiCo2O4 hetero-structure array for electrochemical capacitor. Journal of Power Sources. 2013;239:157–163. Available from: https://doi.org/10.1016/j.jpowsour.2013.03.106
  51. Yang W, Gao Z, Ma J, Wang J, Wang B, Liu L. Effects of solvent on the morphology of nanostructured Co3O 4 and its application for high-performance supercapacitors. Electrochimica Acta. 2013;112:378–385. Available from: https://doi.org/10.1016/j.electacta.2013.08.056
  52. Liu MC, Kong L, Lu C, Li XM, Luo YC, Kang L. Facile fabrication of CoMoO4 nanorods as electrode material for electrochemical capacitors. Materials Letters. 2013;94:197–200. Available from: https://doi.org/10.1016/j.matlet.2012.12.057
  53. Fu W, Wang Y, Han W, Zhang Z, Zha H, Xiea E. Construction of hierarchical ZnCo2O4@NixCo2x(OH)6x core/shell nanowire arrays for high-performance supercapacitors. Journal of Materials Chemistry A. 2016;4:173–182. Available from: https://doi.org/10.1039/c5ta07965a


© 2021 Prasad et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Published By Indian Society for Education and Environment (iSee)


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