Porous carbon prepared via combustion and acid treatment as flexible zinc-ion capacitor electrode material

Electrochemical Zinc Ion Capacitors Enhanced by Redox Reactions of Porous Carbon Cathodes

“…The ZIC can still deliver a gravimetric specific capacitance of 112.2 F g −1 even at a high current density of 60 A g −1 , demonstrating its superior rate capability. Notably, an ultrahigh power density of 48.8 kW kg −1 with a correspondingly high energy density of 40.4 Wh kg −1 can be achieved at a current density of 60 A g −1 , which is the highest value among the ZICs [ 11,13,15,19,20,22,37–43 ] and ZIBs [ 12,44–48 ] reported recently. Considering ZIC with PC800 cathode can deliver twice the energy density and six times the power density of the ZIC with commercial YP‐50F cathode (50.2 Wh kg −1 and 7.4 kW kg −1 ), [ 49 ] we believe our ZIC with PC800 cathode is a promising device for practical energy storage applications.…”

“…Comparison study for the electrochemical performances of PC700, PC800, and PC900 cathodes. a) CV curves recorded at a scan rate of 1 mV s −1 , b) GCD curves of PC800, c) the dependent galvanostatic specific capacities and d) capacitances of PC samples at current densities from 0.1 A g −1 to 20 A g −1 , e) the variation trends for gravimetric specific capacitances, atomic oxygen contents, and areal specific capacitances (normalized by the SSAs) with thermal treatment temperatures of PC samples, f) Ragone curve of PC800 compared with the maximum power density values of zinc ion energy storage devices (ZICs (♦): Zn//1 m Zn(CF 3 SO 3 ) 2 //bioderived porous carbon, [ 11 ] Zn//3M Zn(CFf 3 SO 3 ) 2 //graphene derived porous carbon, [ 13 ] Zn//1 m ZnSO 4 //layered B/N codoped porous carbon, [ 15 ] Zn//2 m ZnSO 4 //activated carbon (AC), [ 19 ] Zn//1 m ZnSO 4 //porous carbon, [ 20 ] Zn//1 m ZnSO 4 //hierarchical porous carbon (HPC), [ 22 ] Zn//2 m ZnSO 4 //AC, [ 37 ] Zn//2 m ZnSO 4 //HPC, [ 38 ] Zn//1 m ZnSO 4 //hollow carbon spheres, [ 39 ] Zn//2 m ZnSO 4 //AC, [ 40 ] Zn//2 m ZnSO 4 //AC, [ 41 ] Zn//2 m ZnSO 4 //graphene oxide film, [ 42 ] Zn//1 m ZnSO 4 //porous carbon nanoflake, [ 43 ] ZIBs (△): Zn//ZnCl 2 //PANI/carbon fiber, [ 12 ] Zn//2 m ZnSO 4 //PTO, [ 44 ] Zn//20 × 10 −3 m ZnSO 4 //CuHCF, [ 45 ] Zn//2 m ZnSO 4 //MnO 2 , [ 46 ] Zn//20 × 10 −3 m ZnSO 4 //CuZnHCF, [ 47 ] Zn//2 m ZnSO 4 //MXene‐rGO 2 , [ 48 ] and M denotes mol L −1 ) reported in recent years.…”

“…[ 19 ] The assembled ZIC delivered a capacity of 272.3 F g −1 and a high power density of 14.9 kW kg −1 with a corresponding energy density of 30 Wh kg −1 in the operational voltage window of 0.2–1.8 V. Liu and co‐workers employed a porous carbon cathode to assemble ZIC. The as‐fabricated ZIC delivered a capacitance of 298.6 F g −1 , a maximum energy density of 82.36 Wh kg −1 , and a maximum power density of up to 3.76 kW kg −1 in the operating voltage range of 0.2–1.8 V. [ 20 ] In another work, Tang and co‐workers reported a ZIC consisted of Zn anode and bioderived porous carbon cathode using 1 m Zn(CF 3 SO 3 ) 2 in acetonitrile (AN) as the electrolyte. [ 11 ] The organic electrolyte enabled a wide operation voltage window of 0–1.8 V so that the ZIC showed a high capacitance of 170 F g −1 and a high energy density of 52.7 Wh kg −1 at a power density of 1.73 kW kg −1 .…”

Ultrathin carbon nanosheets for highly efficient capacitive K-ion and Zn-ion storage

“…Zinc-ion hybrid supercapacitors (ZHSs) have received extensive attentions owing to the rich zinc sources, low cost, and high safety 22,31 . The negative electrode material for ZHSs is usually a carbon-based material with a high specific surface area 32,33 . Therefore, our carefully designed Ca-900 with unique ultrathin hierarchically porous structure shows great potential in ZHSs.…”

Recent progress and challenges of carbon materials for Zn‐ion hybrid supercapacitors

“…Table 1 summarizes the electrochemical performance of the stateof-the-art carbonaceous electrodes for the construction of ZHSCs. [26][27][28][29][30][31][32]39,[45][46][47][48][49][50][51][52][53][54][55][56] A number of methods have been reported to enhance the physical or chemical adsorption to a carbon-positive electrode, including adjustment of morphology, 56 construction of a hierarchical porous structure, 32 and introduction of heteroatomic dopants 51 or functional oxygen groups. 57 Briefly, despite some exciting achievements, the capacity of the most cutting-edge carbon still fails to match the extremely high theoretical capacity of Zn electrodes, making the overall performance of the ZHSC devices utterly disappointing.…”