Composite of Macroporous Carbon with Honeycomb-Like Structure from Mollusc Shell and NiCo₂O₄ Nanowires for High-Performance Supercapacitor

Abstract

Novel biological carbon materials with highly ordered microstructure and large pore volume have caused great interest due to their multifunctional properties. Herein, we report the preparation of an interconnected porous carbon material by carbonizing the organic matrix of mollusc shell. The obtained three-dimensional carbon skeleton consists of hexangular and tightly arranged channels, which endow it with efficient electrolyte penetration and fast electron transfer, enable the mollusc shell based macroporous carbon material (MSBPC) to be an excellent conductive scaffold for supercapacitor electrodes. By growing NiCo2O4 nanowires on the obtained MSBPC, NiCo2O4/MSBPC composites were synthesized. When used on supercapacitor electrode, it exhibited anomalously high specific capacitance (∼1696 F/g), excellent rate performance (with the capacity retention of 58.6% at 15 A/g) and outstanding cycling stability (88% retention after 2000 cycles). Furthermore, an all-solid-state symmetric supercapacitor was also assembled based on this NiCo2O4/MSBPC electrode and showed good electrochemical performance with an energy density of 8.47 Wh/kg at 1 A/g, good stability over 10000 cycles. And we believe that more potential applications beyond energy storage can be developed based on this MSBPC.

One-pot synthesis of CoNiO2 single-crystalline nanoparticles as high-performance electrode materials of asymmetric supercapacitors

“…It can be observed that the specific capacitance gradually increases in the course of initial 500 cycles instead of decreasing. This phenomenon can be attributed to the full activation of the electrodes and also appears in many cycling stability tests in the literatures (Xiong et al 2014;Liang et al 2014). More importantly, the CoNiO 2 //AC ASCs exhibit better cycling performance at each current density.…”

Facile synthesis of polyaniline/NiCo2O4 nanocomposites with enhanced electrochemical properties for supercapacitors

“…Aniline (1 mL) was dissolved in 54 mL of H 2 SO 4 (0.5 M) and stirred well in an ice bath. Certain amounts of NiCo 2 O 4 (5,8,10,15, and 20 wt%) nanopowder were suspended in the above solution and stirred for about 1 h. As an oxidizing agent, 50 mL of precooled solution of ammonium persulfate (0.1 M) was then slowly added drop wise to the mixture with a constant stirring over a period of 2 h. The reaction was then left at 0°C for 4 h. The product obtained was collected by filtration and washed several times by acetone and distilled water until the filtrate was colorless. The product was dried at 80°C for 24 h. Pure polyaniline was synthesized in the same manner without adding NiCo 2 O 4 .…”

“…Active materials are the most crucial factor in governing the electrochemical performance for supercapacitors. Generally, the active materials have three kinds including carbon materials [4,5], conducting polymers [6,7], and transition metal oxides [8,9]. Among all these materials mentioned above, conducting polymers are the most promising materials as they possess redox pseudocapacitance in addition to double-layer capacitance.…”

“…Kong et al [33] had interestingly found that the NiO/NiCo 2 O 4 /Co 3 O 4 -fabricated composite exhibits high specific capacitance of 1717 F g −1 at a current density of 5 mA cm −2 . NiCo 2 O 4 /MSBPC composites that were synthesized by Xiong et al [8] exhibited anomalously high specific capacitance of 1696 F g −1 at 1 A g −1 in a 2 M KOH solution, while the electrochemical properties of NiCo 2 O 4 -doped PANI in H 2 SO 4 solution is seldom been reported. Moreover, in our previous works [34,35], we have investigated that PANI with different doping levels of Ni 2+ and Co 2+ prepared by electrochemical polymerization in acid solution were with better electrochemical performance compared with pure PANI doped with H + .…”

Bio‐Nanotechnology in High‐Performance Supercapacitors

“…[142] Furthermore, the restacking and aggregation of some 1D and two-dimensional (2D) carbon materials, such as GN and CNTs, can cause severe degradation of the electrochemical properties due to the strong van der Waals interactions between the neighboring layers. [143] Hence, lowcost biochars with delicate structures have been studied as raw materials to fabricate metallic oxide/carbon (NiO/C, [140a] Co 3 O 4 /C, [144] NiCo 2 O 4 /C, [145] MnO 2 /C, [146] etc. ), metallic hydroxide/carbon (Ni-Al layered double hydroxide/C [143b] ), Adv.…”