A Superior Potassium-Ion Anode Material from Pitch-based Activated Carbon Fibers with Hierarchical Pore Structure Prepared by Metal Catalytic Activation

Abstract

The pitch-based activated carbon fibers with nickel sulfide nanoparticles (ACF/NiS) were designed by in situ polymerization of ethylene tar with the addition of nickel nitrate followed by melt spinning, stabilization, carbonization, steam activation, and vulcanization processes. The ACF/NiS with hierarchical pore structure and abundant active sites was used as an anode material to improve Coulombic efficiency and increase capacity of potassium-ion batteries (PIBs). The results showed the obtained ACF/NiS with excellent specific surface area of 1552 m 2 g −1 and high mesopore volume contribution of 38%, which delivered a high initial Coulombic efficiency of 84.22%, a high capacity of 292.5 mAh g −1 , and retained 95.7% capacity retention after 200 cycles at 0.5 A g −1 current density. The NiS provided abundant active sites for the adsorption of potassium-ion, and the rich hierarchical structure shortened the electrolyte penetration path and expanded the storage space of potassium-ion, making it easier to store potassium-ion inside the ACF/NiS anode to obtain a better performance. This work presented one strategy for designing the hierarchical pore structure of pitch-based ACF to boost the capacity storage of PIBs and revealed that ACF-based carbon materials served as potential anodes for high-performance PIBs.

Research progress on carbon materials as negative electrodes in sodium‐ and potassium‐ion batteries

“…SIBs and PIBs have received considerable attention in current power supply systems. [94][95][96][97][98] Carbon materials have a variety of structures and morphologies, which have a crucial influence on their Na + /K + storage mechanism.…”

Ni3S2–Ni Hybrid Nanospheres with Intra‐Core Void Structure Encapsulated in N‐Doped Carbon Shells for Efficient and Stable K‐ion Storage

“…[ 39 ] The cathodic peak at 0.8 V in subsequent cycles was caused by the reduction of Ni 3 S 2 to Ni 0 , [ 40 ] and the anodic peak at 2.5 V could be attributed to the oxidation of Ni 0 and K 2 S to Ni 3 S 2 . [ 41 ] The subsequent cycle curves had good overlap, indicating that Ni 3 S 2 ‐Ni@NC‐AE possessed good reversibility during potassium/depotassium process. Moreover, it could be found that Ni 3 S 2 ‐Ni@NC‐AE had a higher peak current and sharper peak compared to the electrodeposited NiS (Figure S9 , Supporting Information), which illustrated that the Ni 3 S 2 ‐Ni@NC‐AE had a good potassium storage reaction kinetics.…”

N, S-co-doped carbon/Co1-xS nanocomposite with dual-enzyme activities for a smartphone-based colorimetric assay of total cholesterol in human serum

“…Generally speaking, the D band is characteristic of disordered carbon or graphite structural defects, whereas the G band is associated with the level of graphitization [36]. The peak intensity ratios for the D-G band (I D /I G ) of NSC and NSC/Co 1-x S were 1.41 and 1.34, respectively, implying an abundance of defects in the porous structure [37]. The slightly lower I D /I G value for NSC/ Co 1-x S might indicate that graphitization was reduced by doping sulfur cobalt in the pyrolysis process [35].…”