Bacterial-Derived, Compressible, and Hierarchical Porous Carbon for High-Performance Potassium-Ion Batteries

Abstract

Hierarchical-structured electrodes having merits of superior cycling stability and high rate performance are highly desired for next-generation energy storage. For the first time, we reported a compressible and hierarchical porous carbon nanofiber foam (CNFF) derived from a sustainable and abundant biomaterial resource, bacterial cellulose, for boosting the electrochemical performance of potassium-ion batteries. The CNFF free-standing electrode with a hierarchical porous three-dimensional structure demonstrated excellent rate performance and outstanding cyclic stability in the extended cycling test. Specifically, in the long-term cycling-stability test, the CNFF electrode maintained a stable capacity of 158 mA h g–1 after 2000 cycles at a high current density of 1000 mA g–1, which has an average capacity decay of 0.006% per cycle. After that, the CNFF electrode maintained a capacity of 141 mA h g–1 at a current density of 2000 mA g–1 for another 1500 cycles, and a capacity of 122 mA h g–1 at a current density of 5000 mA g–1 for an additional 1000 cycles. The mechanism for the outstanding performance is that the hierarchical porous and stable CNFF with high surface area and high electronic conductivity provides sufficient sites for potassium-ion storage. Furthermore, quantitative kinetics analysis has validated the capacitive- and diffusion-controlled charge-storage contributions in the carbon-foam electrode. This work will inspire the search for cost-effective and sustainable materials for potassium electrochemical energy storage.

Rhenium Diselenide Anchored on Reduced Graphene Oxide as Anode with Cyclic Stability for Potassium‐Ion Battery

“…The N 2 adsorption–desorption isotherms of ReSe 2 @rGO in Figure d shows the typical type‐IV behavior (in IUPAC convention), indicating the existence of a great number of mesopores (2–50 nm) in the sample, which is consistent with the results of the pore diameter distribution plot as shown in the inset of Figure d . Based on the Brunauer–Emmett–Teller (BET) method, the total surface area of the ReSe 2 @rGO sample exhibited a specific surface area of 32.071 m 2 g −1 , larger than that of pure ReSe 2 , which was determined to be 12.729 m 2 g −1 .…”

A Site‐Selective Doping Strategy of Carbon Anodes with Remarkable K‐Ion Storage Capacity

“…capacity of 305 mAh g À1 , test lasted for 3 months) which is much higher than most recently reported carbon anodes. [27,47] In comparison, the ENDC700 electrode shows a capacity retention of 73 % with a remaining capacity of 193 mAh g À1 after 300 cycles. The NDC900 electrode shows the lowest remaining capacity of only 62 mAh g À1 after 420 cycles.…”

“…[23][24][25][26] To compete with the LIB technology or achieve a low energy storage cost, the capacity of carbonaceous anodes of PIB should be improved to be comparable to the specific capacity of LiC 6 . For the sake of enhanced capacity of carbonaceous anodes in PIB, several parameters must be carefully controlled, including 1) the (002) lattice spacing should be made large enough for efficient (de)potassiation; [27,28] 2) the defect-induced adsorption mechanism should be engineered to enhance K-ion storage beyond the intercalation mechanism (here, defects refer to CÀC sp 3 defects, and heteroatom-doping-induced defects). [23,24,29] Nitrogen-doping has been demonstrated as an efficient way to enhance the potassium storage capacities of carbonaceous materials owing to the increased electron negativity of defective sites for efficient adsorption of Kions.…”

Carbon Anodes for Nonaqueous Alkali Metal‐Ion Batteries and Their Thermal Safety Aspects

“…Energy Mater. [177] Heteroatomic doping has been an effective tool for enhancing electrochemical performance with PIB carbon anodes, with nitrogen-rich hard carbon microspheres obtaining a capacity of 154 mAh g −1 at an immense 72 C rate, due to the enhanced adsorption capability and electronic conductivity. [175,176] Similarly, a carbon nanofiber foam exhibited a low capacity decay of 0.006% per cycle after 1000 cycles at 1 A g −1 due to the highly porous structure and capacitive-like storage mechanism.…”