Effective enhancement of electrochemical energy storage of cobalt-based nanocrystals by hybridization with nitrogen-doped carbon nanocages

  • Qingming Ma (麻青明)
  • Yuejian Yao (姚月坚)
  • Minglei Yan (闫明磊)
  • Jie Zhao (赵杰)
  • Chengxuan Ge (葛承宣)
  • Qiang Wu (吴强)Email author
  • Lijun Yang (杨立军)
  • Xizhang Wang (王喜章)
  • Zheng Hu (胡征)Email author


Cobalt-based oxygenic compounds Co(OH)2, CoO and Co3O4 are attractive for electrochemical energy storage owing to their high theoretical capacities and pseudocapacitive properties. Despite the great efforts to their compositional and morphological regulations, the performances to date are still quite limited owing to the low active surface area and sluggish charge transfer kinetics. Herein, different Co-based nanocrystals (Co-NCs) were conveniently anchored on the hierarchical nitrogen-doped carbon nanocages (hNCNCs) with high specific surface area and coexisting micro-meso-macropores to decrease the size and facilitate the charge transfer. Accordingly, a high specific capacity of 1170 F g−1 is achieved at 2 A g−1 for the Co(OH)2/hNCNCs hybrid, in which the capacitance of Co(OH)2 (2214 \({\rm{F\;g}}_{\rm{Co({OH})_2}}^{ - 1}\)) is approaching to its theoretical maximum (2595 F g−1), demonstrating the high utilization of active materials by the hybridization with N-doped nanocarbons. This study also reveals that these Co-NCs store/release electrical energy via the same reversible redox reaction despite their different pristine compositions. This insight on the energy storage of Co-based nanomaterials suggests that the commonly-employed transformation of the Co-NCs from Co(OH)2 to CoO and Co3O4 on carbon supports is unnecessary and even could be harmful to the energy storage performance. The result is instructive to develop high-energy-density electrodes from transition metal compounds.


Co-based nanocrystals pseudocapacitance hybridization N-doped carbon nanocages supercapacitors 

钴基纳米晶-氮掺杂碳纳米笼复合材料的构建与 电化学储能性能研究


Co(OH)2、CoO和Co3O4等钴基化合物因具有高理论容量和 赝电容性质而备受关注. 但受限于活性表面积小、电荷传输缓慢, 钴基纳米材料的实际储能性能却有限. 本文以我们前期开发的具 有大比表面积、高导电性和微孔-介孔-大孔共存的分级结构氮掺 杂碳纳米笼(hNCNCs)为载体, 成功构建了晶粒尺寸小、电荷转移 快的系列钴基纳米晶-hNCNCs复合材料, 有效地提高了活性材料 的利用率. 其中, Co(OH)2/hNCNCs在2 A g−1下表现出1170 F g−1的 高比容量, 基于活性物种Co(OH)2的比电容高达2214 F g−1, 接近其 理论值(2595 F g−1). 研究发现, 具有不同组成的Co(OH)2、CoO和 Co3O4纳米晶通过相同的可逆氧化还原反应存储/释放电能. 这种新 的储能机理表明将碳基载体上的Co(OH)2转化为CoO或Co3O4的策 略是提升储能性能的非必要条件, 还可能损害其储能性能. 本研究 可为开发过渡金属化合物基高能量密度电极材料提供借鉴.



This work was jointly supported by the National Key Research and Development Program of China (2017YFA0206500 and 2018YFA0209103), the National Natural Science Foundation of China (21832003, 21773111, 51571110 and 21573107), and the Fundamental Research Funds for the Central Universities (020514380126).

Supplementary material

40843_2019_9449_MOESM1_ESM.pdf (4.5 mb)
Effective enhancement of electrochemical energy storage of cobalt-based nanocrystals by hybridization with nitrogen-doped carbon nanocages


  1. 1.
    Winter M, Brodd RJ. What are batteries, fuel cells, and supercapacitors? Chem Rev, 2004, 104: 4245–4270CrossRefGoogle Scholar
  2. 2.
    Goodenough JB. Evolution of strategies for modern rechargeable batteries. Acc Chem Res, 2013, 46: 1053–1061CrossRefGoogle Scholar
  3. 3.
    Wang G, Zhang L, Zhang J. A review of electrode materials for electrochemical supercapacitors. Chem Soc Rev, 2012, 41: 797–828CrossRefGoogle Scholar
  4. 4.
    Lai H, Wu Q, Zhao J, et al. Mesostructured NiO/Ni composites for high-performance electrochemical energy storage. Energy Environ Sci, 2016, 9: 2053–2060CrossRefGoogle Scholar
  5. 5.
    Cheng F, Liang J, Tao Z, et al. Functional materials for rechargeable batteries. Adv Mater, 2011, 23: 1695–1715CrossRefGoogle Scholar
  6. 6.
    Wang J, Dong S, Ding B, et al. Pseudocapacitive materials for electrochemical capacitors: from rational synthesis to capacitance optimization. Nat Sci Rev, 2016, 7: nww072CrossRefGoogle Scholar
  7. 7.
    Chen X, Paul R, Dai L. Carbon-based supercapacitors for efficient energy storage. Natl Sci Rev, 2017, 4: 453–489CrossRefGoogle Scholar
  8. 8.
    Jiang H, Lee PS, Li C. 3D carbon based nanostructures for advanced supercapacitors. Energy Environ Sci, 2013, 6: 41–53CrossRefGoogle Scholar
  9. 9.
    Conway BE. Electrochemical Supercapacitors: Scientific Fundamentals and Technological Applications. New York: Kluwer Academic/Plenum Publishers, 1999CrossRefGoogle Scholar
  10. 10.
    Simon P, Gogotsi Y, Dunn B. Where do batteries end and supercapacitors begin? Science, 2014, 343: 1210–1211CrossRefGoogle Scholar
  11. 11.
    Augustyn V, Simon P, Dunn B. Pseudocapacitive oxide materials for high-rate electrochemical energy storage. Energy Environ Sci, 2014, 7: 1597–1614CrossRefGoogle Scholar
  12. 12.
    Zhu YG, Wang Y, Shi Y, et al. CoO nanoflowers woven by CNT network for high energy density flexible micro-supercapacitor. Nano Energy, 2014, 3: 46–54CrossRefGoogle Scholar
  13. 13.
    Jagadale AD, Jamadade VS, Pusawale SN, et al. Effect of scan rate on the morphology of potentiodynamically deposited β-Co(OH)2 and corresponding supercapacitive performance. Electrochim Acta, 2012, 78: 92–97CrossRefGoogle Scholar
  14. 14.
    Wang R, Yan X, Lang J, et al. A hybrid supercapacitor based on flower-like Co(OH)2 and urchin-like VN electrode materials. J Mater Chem A, 2014, 2: 12724–12732CrossRefGoogle Scholar
  15. 15.
    Salunkhe RR, Tang J, Kamachi Y, et al. Asymmetric supercapacitors using 3D nanoporous carbon and cobalt oxide electrodes synthesized from a single metal-organic framework. ACS Nano, 2015, 9: 6288–6296CrossRefGoogle Scholar
  16. 16.
    Zhao T, Jiang H, Ma J. Surfactant-assisted electrochemical deposition of α-cobalt hydroxide for supercapacitors. J Power Sources, 2011, 196: 860–864CrossRefGoogle Scholar
  17. 17.
    Yang S, Liu Y, Hao Y, et al. Oxygen-vacancy abundant ultrafine Co3O4/graphene composites for high-rate supercapacitor electrodes. Adv Sci, 2018, 5: 1700659CrossRefGoogle Scholar
  18. 18.
    Xia X, Tu J, Zhang Y, et al. Freestanding Co3O4 nanowire array for high performance supercapacitors. RSC Adv, 2012, 2: 1835–1841CrossRefGoogle Scholar
  19. 19.
    Mei J, Fu W, Zhang Z, et al. Vertically-aligned Co3O4 nanowires interconnected with Co(OH)2 nanosheets as supercapacitor electrode. Energy, 2017, 139: 1153–1158CrossRefGoogle Scholar
  20. 20.
    Xiang K, Xu Z, Qu T, et al. Two dimensional oxygen-vacancy-rich Co3O4 nanosheets with excellent supercapacitor performances. Chem Commun, 2017, 53: 12410–12413CrossRefGoogle Scholar
  21. 21.
    Zhou C, Zhang Y, Li Y, et al. Construction of high-capacitance 3D CoO@polypyrrole nanowire array electrode for aqueous asymmetric supercapacitor. Nano Lett, 2013, 13: 2078–2085CrossRefGoogle Scholar
  22. 22.
    Wang Z, Liu Y, Gao C, et al. A porous Co(OH)2 material derived from a MOF template and its superior energy storage performance for supercapacitors. J Mater Chem A, 2015, 3: 20658–20663CrossRefGoogle Scholar
  23. 23.
    Pang H, Li X, Zhao Q, et al. One-pot synthesis of heterogeneous Co3O4-nanocube/Co(OH)2-nanosheet hybrids for high-performance flexible asymmetric all-solid-state supercapacitors. Nano Energy, 2017, 35: 138–145CrossRefGoogle Scholar
  24. 24.
    Jing M, Yang Y, Zhu Y, et al. An asymmetric ultracapacitors utilizing α-Co(OH)2/Co3O4 flakes assisted by electrochemically alternating voltage. Electrochim Acta, 2014, 141: 234–240CrossRefGoogle Scholar
  25. 25.
    Xue T, Wang X, Lee JM. Dual-template synthesis of Co(OH)2 with mesoporous nanowire structure and its application in supercapacitor. J Power Sources, 2012, 201: 382–386CrossRefGoogle Scholar
  26. 26.
    Zheng C, Cao C, Ali Z, et al. Enhanced electrochemical performance of ball milled CoO for supercapacitor applications. J Mater Chem A, 2014, 2: 16467–16473CrossRefGoogle Scholar
  27. 27.
    Zhou Y, Zou X, Zhao Z, et al. CoO/rGO composite prepared by a facile direct-flame approach for high-power supercapacitors. Ceramics Int, 2018, 44: 16900–16907CrossRefGoogle Scholar
  28. 28.
    Patil UM, Nam MS, Sohn JS, et al. Controlled electrochemical growth of Co(OH)2 flakes on 3D multilayered graphene foam for high performance supercapacitors. J Mater Chem A, 2014, 2: 19075–19083CrossRefGoogle Scholar
  29. 29.
    Jiang J, Liu J, Ding R, et al. Large-scale uniform a-Co(OH)2 long nanowire arrays grown on graphite as pseudocapacitor electrodes. ACS Appl Mater Interfaces, 2011, 3: 99–103CrossRefGoogle Scholar
  30. 30.
    Zhang F, Yuan C, Zhu J, et al. Flexible films derived from electrospun carbon nanofibers incorporated with Co3O4 hollow nanoparticles as self-supported electrodes for electrochemical capacitors. Adv Funct Mater, 2013, 23: 3909–3915CrossRefGoogle Scholar
  31. 31.
    Wang H, Qing C, Guo J, et al. Highly conductive carbon-CoO hybrid nanostructure arrays with enhanced electrochemical performance for asymmetric supercapacitors. J Mater Chem A, 2014, 2: 11776–11783CrossRefGoogle Scholar
  32. 32.
    Zhang F, Yuan C, Lu X, et al. Facile growth of mesoporous Co3O4 nanowire arrays on Ni foam for high performance electrochemical capacitors. J Power Sources, 2012, 203: 250–256CrossRefGoogle Scholar
  33. 33.
    Gao Y, Chen S, Cao D, et al. Electrochemical capacitance of Co3O4 nanowire arrays supported on nickel foam. J Power Sources, 2010, 195: 1757–1760CrossRefGoogle Scholar
  34. 34.
    Patil UM, Lee SC, Sohn JS, et al. Enhanced symmetric supercapacitive performance of Co(OH)2 nanorods decorated conducting porous graphene foam electrodes. Electrochim Acta, 2014, 129: 334–342CrossRefGoogle Scholar
  35. 35.
    Yang W, Qu G, Chen M, et al. Effective NaBH4-exfoliated ultrathin multilayer Co(OH)2 nanosheets arrays and sulfidation for energy storage. Nanotechnology, 2018, 29: 295403CrossRefGoogle Scholar
  36. 36.
    Wu Q, Yang L, Wang X, et al. From carbon-based nanotubes to nanocages for advanced energy conversion and storage. Acc Chem Res, 2017, 50: 435–444CrossRefGoogle Scholar
  37. 37.
    Feng H, Ma J, Hu Z. Nitrogen-doped carbon nanotubes functionalized by transition metal atoms: A density functional study. J Mater Chem, 2010, 20: 1702–1708CrossRefGoogle Scholar
  38. 38.
    Zhang Z, Chen Y, Zhou L, et al. The simplest construction of single-site catalysts by the synergism of micropore trapping and nitrogen anchoring. Nat Commun, 2019, 10: 1657CrossRefGoogle Scholar
  39. 39.
    Zhao J, Lai H, Lyu Z, et al. Hydrophilic hierarchical nitrogen-doped carbon nanocages for ultrahigh supercapacitive performance. Adv Mater, 2015, 27: 3541–3545CrossRefGoogle Scholar
  40. 40.
    Pralong V, Delahaye-Vidal A, Beaudoin B, et al. Oxidation mechanism of cobalt hydroxide to cobalt oxyhydroxide. J Mater Chem, 1999, 9: 955–960CrossRefGoogle Scholar
  41. 41.
    Chen S, Wang L, Wu Q, et al. Advanced non-precious electrocatalyst of the mixed valence CoOx nanocrystals supported on N-doped carbon nanocages for oxygen reduction. Sci China Chem, 2015, 58: 180–186CrossRefGoogle Scholar
  42. 42.
    Zhang Z, Wu Q, Mao K, et al. Efficient ternary synergism of platinum/tin oxide/nitrogen-doped carbon leading to high-performance ethanol oxidation. ACS Catal, 2018, 8: 8477–8483CrossRefGoogle Scholar
  43. 43.
    Oktaviano HS, Yamada K, Waki K. Nano-drilled multiwalled carbon nanotubes: Characterizations and application for LIB anode materials. J Mater Chem, 2012, 22: 25167–25173CrossRefGoogle Scholar
  44. 44.
    Li Z, Duan H, Shao M, et al. Ordered-vacancy-induced cation intercalation into layered double hydroxides: A general approach for high-performance supercapacitors. Chem, 2018, 4: 2168–2179CrossRefGoogle Scholar
  45. 45.
    Zou Y, Kinloch IA, Dryfe RAW. Mesoporous vertical Co3O4 nanosheet arrays on nitrogen-doped graphene foam with enhanced charge-storage performance. ACS Appl Mater Interfaces, 2015, 7: 22831–22838CrossRefGoogle Scholar
  46. 46.
    Lee KK, Chin WS, Sow CH. Cobalt-based compounds and composites as electrode materials for high-performance electrochemical capacitors. J Mater Chem A, 2014, 2: 17212–17248CrossRefGoogle Scholar

Copyright information

© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Qingming Ma (麻青明)
    • 1
  • Yuejian Yao (姚月坚)
    • 1
  • Minglei Yan (闫明磊)
    • 1
  • Jie Zhao (赵杰)
    • 1
  • Chengxuan Ge (葛承宣)
    • 1
  • Qiang Wu (吴强)
    • 1
    Email author
  • Lijun Yang (杨立军)
    • 1
  • Xizhang Wang (王喜章)
    • 1
  • Zheng Hu (胡征)
    • 1
    Email author
  1. 1.Key Laboratory of Mesoscopic Chemistry of MOE and Jiangsu Provincial Lab for Nanotechnology, School of Chemistry and Chemical EngineeringNanjing UniversityNanjingChina

Personalised recommendations