[1] [1] YANG Y. A mini-review: Emerging all-solid-state energy storage electrode materials for flexible devices[J]. Nanoscale, 2020, 12(6): 3560-3573.

[3] [3] SUN H, ZHU J, BAUMANN D, et al. Hierarchical 3D electrodes for electrochemical energy storage[J]. Nat Rev Mater, 2019, 4(1): 45-60.

[5] [5] YANG Y, HE L, TANG C, et al. Improved conductivity and capacitance of interdigital carbon microelectrodes through integration with carbon nanotubes for micro-supercapacitors[J]. Nano Res, 2016, 9(8): 2510-2519.

[6] [6] SHI X, ZENG Z, LIAO C, et al. Flexible, planar integratable and all-solid-state micro-supercapacitors based on nanoporous gold/manganese oxide hybrid electrodes via template plasma etching method[J]. J Alloys Compds, 2018, 739: 979-986.

[7] [7] XIAO Y, HUANG L, ZHANG Q, et al. Gravure printing of hybrid MoS2@S-rGO interdigitated electrodes for flexible microsupercapacitors[J]. Appl Phys Lett, 2015, 107(1): 013906.

[8] [8] LOCHMANN S, GROTHE J, ECKHARDT K, et al. Nanoimprint lithography of nanoporous carbon materials for micro-supercapacitor architectures[J]. Nanoscale, 2018, 10(21): 10109-10115.

[9] [9] WANG Y, SONG Y, XIA Y. Electrochemical capacitors: Mechanism, materials, systems, characterization and applications[J]. Chem Soc Rev, 2016, 45 (21), 5925-5950.

[11] [11] LI X, ZHANG J, SHEN L, et al. Preparation and characterization of graphitic carbon nitride through pyrolysis of melamine[J]. Appl Phys A, 2009, 94(2): 387-392.

[12] [12] NAGARAJU G, CHA S M, SEKHAR S C, et al. Metallic layered polyester fabric enabled nickel selenide nanostructures as highly conductive and binderless electrode with superior energy storage performance[J]. Adv Energy Mater, 2016, 7(4): 1601362.

[13] [13] GOPI CVVM, REDDY A E, KIM H J. Wearable superhigh energy density supercapacitors using hierarchical ternary metal selenides composite of CoNiSe2 microspheres decorated with CoFe2Se4 nanorods[J]. J Mater Chem A, 2018, 6(17): 7439-7448.

[14] [14] PU J, WANG T T, WANG H Y, et al. Direct growth of NiCo2S4 nanotube arrays on nickel foam as high-performance binder-free electrodes for supercapacitors[J]. Chem Plus Chem, 2014, 79(4): 577-583.

[15] [15] WAN H, JIANG J, YU J, et al. NiCo2S4 porous nanotubes synthesis via sacrificial templates: High-performance electrode materials of supercapacitors[J]. Cryst Eng Comm, 2013, 15(38): 7649-7651.

[16] [16] BAO J, ZHANG X, FAN B, et al. Ultrathin spinel-structured nanosheets rich in oxygen deficiencies for enhanced electrocatalytic water oxidation[J]. Angewandte Chemie, 2015, 127(25): 7507-7512.

[17] [17] SHEN L, WANG J, XU G, et al. NiCo2S4 nanosheets grown on nitrogen-doped carbon foams as an advanced electrode for supercapacitors[J]. Adv Energy Mater, 2015, 5(3): 1400977.

[18] [18] YANG L, ZHANG J, WANG S, et al. Facilely constructing 3D porous NiCo2S4 nanonetworks for high-performance supercapacitors[J]. New J Chem, 2014, 38(9): 4045-4048.

[19] [19] HAN X, ZHANG W, MA X, et al. Identifying the activation of bimetallic sites in NiCo2S4@g-C3N4-CNT hybrid electrocatalysts for synergistic oxygen reduction and evolution[J]. Adv Mater, 2019, 31(18): 1808281.

[21] [21] MA Y, SHENG H, DOU W, et al. Fe2O3 nanoparticles anchored on the Ti3C2Tx MXene paper for flexible supercapacitors with ultrahigh volumetric capacitance[J]. ACS Appl Mater Interfaces, 2020, 12(37): 41410-41418.

[24] [24] ZHU Y, JI X, WU Z, et al. NiCo2S4 hollow microsphere decorated by acetylene black for high-performance asymmetric supercapacitor[J]. Electrochim Acta, 2015, 186: 562-571.

[25] [25] XIAO Y, SU D, WANG X, et al. In situ growth of ultradispersed NiCo2S4 nanoparticles on graphene for asymmetric supercapacitors[J]. Electrochim Acta, 2015, 176: 44-50.

[26] [26] WANG H, YANG Y, ZHOU X, et al. NiCo2S4/tryptophan- functionalized graphene quantum dot nanohybrids for high-performance supercapacitors[J]. New J Chem, 2017, 41(3): 1110-1118.

[27] [27] WANG Z, HE B, KONG W, et al. Synthesis of NiCo2S4 nanocages as pseudocapacitor electrode materials[J]. Chem Select, 2016, 1(13): 4082-4086.

[28] [28] CHEN H, LIU X L, ZHANG J M, et al. Rational synthesis of hybrid NiCo2S4@MnO2 heterostructures for supercapacitor electrodes[J]. Ceram Int, 2016, 42(7): 8909-8914.

[29] [29] WANG T, LE Q, ZHANG G, et al. Facile preparation and sulfidation analysis for activated multiporous carbon@NiCo2S4 nanostructure with enhanced supercapacitive properties[J]. Electrochim Acta, 2016, 211: 627-635.

[30] [30] LI Z, QU Y, WANG M, et al. O/W interface-assisted hydrothermal synthesis of NiCo2S4 hollow spheres for high-performance supercapacitors[J]. Colloid Polym Sci, 2016, 294(8): 1325-1332.

[31] [31] FU W, ZHAO C, HAN W, et al. Cobalt sulfide nanosheets coated on NiCo2S4 nanotube arrays as electrode materials for high-performance supercapacitors[J]. J Mater Chem A, 2015, 3(19): 10492-10497.

[32] [32] TANG Y, CHEN T, YU S, et al. A highly electronic conductive cobalt nickel sulphide dendrite/quasi-spherical nanocomposite for a supercapacitor electrode with ultrahigh areal specific capacitance[J]. J Power Sources, 2015, 295: 314-322.

[33] [33] XIAO H, WU Z S, CHEN L, et al. One-step device fabrication of phosphorene and graphene interdigital micro-supercapacitors with high energy density[J]. ACS Nano, 2017, 11(7): 7284-7292.