Mesoporous carbon nanosheet-assembled flowers towards superior potassium storage

Potassium-ion batteries (PIBs) are attracted tremendous interest for large-scale energy storage systems (ESSs) owing to their economic merits. However, the main challenges of the PIBs are sluggish K-ion diffusion and large volume variations in the potassium repeated intercalation/deintercalation. Herein, mesoporous carbon nanosheet-assembled flowers (abbreviated as F-C) are designed as an original anode for superior-performance PIBs. Specifically, the F-C anode exhibits a high K-storage capacity (e.g., 381 mAh/g at 50 mA/g during the 2nd cycle), excellent rate performance (e.g., 101 mAh/g at 2.0 A/g) and superior long cycle capability. Such excellent K-ion storage property is largely benefited from the large surface area (similar to 141 m(2)/g) and reasonable pore volume (0.465 cm(3)/g), which not only stimulates rapid K-ions diffusion and relieves the huge volume strain, but also exposes extensive active sites for K-ion capacitive storage. (C) 2020 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

Mesoporous carbon nanosheet-assembled flowers exhibit high potassium storage capacity, excellent rate performance, and superior long cycle capability, mainly due to their large surface area and reasonable pore volume.