Small mesopore engineering of pitch-based porous carbons toward enhanced supercapacitor performance

Hierarchically Porous N, P-Codoped Carbon Materials for High-Performance Supercapacitors

“…NP-C600 and NP-C700 display a representative type-I isotherm (Figure A), revealing a double-layer adsorption curve of micropores, , while NP-C800 depicts a typical type-II isotherm with a large hysteresis ring, rendering a large number of mesopores. , The SSA of NP-C700, as measured, is 942.9 m 2 g –1 , which is significantly larger than those of NP-C600 (570.3 m 2 g –1 ) and NP-C800 (303.5 m 2 g –1 ), indicating that the calcination temperature plays a key role in regulating the surface area and porous structure. , Properly increasing the carbonization temperature can be of great benefit for enlarging the SSA and inducing pore hierarchy for high-energy/rate supercapacitors . However, overly high-temperature annealing may cause the collapse of microporous and small-sized structures especially under the circumstance of deficient KOH. , The pore-size distribution curves in Figure B exhibit that all samples possess micropores and small-sized mesopores ranging from 0.5 to 10 nm, which are resulted from KOH activation and partial removal of carbon fragments. ,, It should be noted that NP-C700 has much more intensified micropores and mesopores, which is in good agreement with its largest SSA obtained from N 2 absorption/desorption isotherms. , …”

“…33 However, overly high-temperature annealing may cause the collapse of microporous and small-sized structures especially under the circumstance of deficient KOH. 43,44 The pore-size distribution curves in Figure 2B exhibit that all samples possess micropores and small-sized mesopores ranging from 0.5 to 10 nm, which are resulted from KOH activation and partial removal of carbon fragments. 1,40,45 It should be noted that NP-C700 has much more intensified micropores and mesopores, which is in good agreement with its largest SSA obtained from N 2 absorption/desorption isotherms.…”

Preparation of N/O-codoped quinoline pitch-based porous carbons for high-quality supercapacitor electrodes

“…5,21 Moreover, it is found that small mesopores in the size of 2-5 nm are of great help in maximizing supercapacitive performance. 26 On the other hand, doping of active heteroatoms (N, O, S, P and B) is also thought to be an effective way to improve the electrochemical performance of porous carbons, as it can not only provide additional pseudo-capacitance via faradaic reactions, but also raise the conductivity of the carbon skeleton and the wettability of the carbon surface. 14,19,27 At present, codoping is gaining huge attention considering the synergistic effect of distinct heteroatoms, where doping N/O is viewed as the most exciting strategy to boost the capacity performance of porous carbon.…”

Synthesis and characterization of PI gel carbonized material and its use in a supercapacitor

“…Carbon materials have been studied extensively as electrode materials for flexible supercapacitors because of their superior mechanical and double-layer capacitive properties. [15][16][17] Among many polymer materials, aromatic polyimides with rigid chains and considerable steric hindrance are potential membrane materials for preparing C-C composite structures. 18,19 In addition, in the process of high-temperature degradation, this method is widely used in the pore-forming process due to the emission of gas products.…”