Nitrogen/sulphur dual-doped hierarchical carbonaceous fibers boosting potassium-ion storage

• 作者: Junzhi Li Junming Cao Xifei Li Junhua Hu Yaohui Zhang Hirbod Maleki Kheimeh Sari Chunxiao Lv Igor.V.Zatovsky Wei Han
• 来源期刊: 能源化学
• 年，卷（期）: 2021,（4）
• 页码范围: 420-427
• 页数: 8页
• 语种: 英文

摘要

The carbon materials as anode electrodes have been widely studied for potassium ion batteries(PIBs).However,the large size of potassium ions prevents their intercalation/deintercalation,resulting in poor storage behaviors.Herein,a novel design of N/S codoped hierarchical carbonaceous fibers(NSHCF)formed from nanosheets self-assembled by catalyzing Aspergillus niger with Sn is reported.The as-prepared NSHCF at 600℃(NSHCF-600)exhibits a high reversible capacity of 345.4 mAh g-1 at 0.1 A g-1 after 100 cycles and an excellent rate performance of 124.5 mAh g-1 at 2 A g-1.The excellent potassium storage performance can be ascribed to the N/S dual-doping,which enlarges interlayer spacing(0.404 nm)and introduces more defects.The larger interlayer spacing and higher pyridinic N active sites can promote K ions diffusion and storage.In addition,the ex situ transmission electron microscopy reveals the high reversibility of potassiation/depotassiation process and structural stability.