Interconnected carbon nanocapsules with high N/S co-doping as stable and high-capacity potassium-ion battery anode

作     者：Honghui Bi Xiaojun He Lei Yang Hongqiang Li Biyu Jin Jieshan Qiu Honghui Bi;Xiaojun He;Lei Yang;Hongqiang Li;Biyu Jin;Jieshan Qiu

作者机构：School of Chemistry and Chemical EngineeringAnhui Key Laboratory of Coal Clean Conversion and High Valued UtilizationKey Lab of Metallurgical Emission Reduction&Resources RecyclingMinistry of EducationAnhui University of TechnologyMaanshan 243002AnhuiChina College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2022年第31卷第3期

页      面：195-204,I0007页

核心收录：

学科分类：0820[工学-石油与天然气工程] 0808[工学-电气工程] 07[理学] 08[工学] 070205[理学-凝聚态物理] 0817[工学-化学工程与技术] 0807[工学-动力工程及工程热物理] 0827[工学-核科学与技术] 0703[理学-化学] 0702[理学-物理学] 

基　　金：the financial supports from the National Natural Science Foundation of China(Grant Nos.51872005 U1508201 52072002)。 

主　　题：3D Carbon nanocapsules N/S co-doping Carbon anode Potassium-ion battery 

摘      要：Carbonaceous materials have drawn much attention in potassium-ion batteries (PIBs) due to their low price and superior physicochemical properties. However, the application of carbonaceous materials in PIB anodes is hindered by sluggish kinetics and large volume expansion. Herein, N/S co-doped carbon nanocapsule (NSCN) is constructed for superior K+ storage. The NSCN possesses 3D nanocapsule framework with abundant meso/macropores, which guarantees structural robustness and accelerates ions/electrons transportation. The high-level N/S co-doping in carbon matrix not only generates ample defects and active sites for K+ adsorption, but also expands interlayer distance for facile K+ intercalation/deintercalation. As a result, the NSCN electrode delivers a high reversible capacity (408 mAh g^(−1) at 0.05 A g^(−1)), outstanding rate capability (149 mAh g^(−1) at 5 A g^(−1)) and favorable cycle stability (150m Ah g^(−1) at 2 A g^(−1) after 2000 cycles). Ex situ TEM, Raman and XPS measurements demonstrate the excellent stability and reversibility of NSCN electrode during potassiation/depotassiation process. This work provides inspiration for the optimization of energy storage materials by structure and doping engineering.