Bagasse-Derived Hard Carbon Anode with an Adsorption–Intercalation Mechanism for High-Rate Potassium Storage
Ting Zhu, Bo Mai, Ping Hu, Congcong Cai, Boyu Xing, Zihe Wei, Changliang Chen, Hao Fan, Mufang Li, Xuanpeng Wang
Abstract
Hard carbon is a kind of abundant-resource and cost-effective anode material for potassium-ion batteries to realize commercialization shortly. However, the poor rate performance and ambiguous energy storage mechanism of hard carbon remain great bottlenecks. In this study, bagasse-pyrolyzed hard carbon (BC) is prepared by the pyrolysis of bagasse, which exhibits a larger surface area and better electrical conductivity than sugarcane-pyrolyzed hard carbon (SC). The BC exhibits a high reversible capacity of 235 mAh g –1 at 100 mA g –1 and a high rate (161 mAh g –1 at 1000 mA g –1 ) for K + storage, which are better than those of SC (108 mAh g –1 and 49 mAh g –1 ). In situ X-ray diffraction and Raman results reveal the “adsorption–intercalation” K + storage mechanism and prove that the favorable defects endow BC with better electrochemical capability.