Hard carbon derived from biomass is regarded as a promising anode material for sodium-ion batteries(SIBs)because of its low operating potential,high capacity,resource availability,and low cost.However,scientific and t...Hard carbon derived from biomass is regarded as a promising anode material for sodium-ion batteries(SIBs)because of its low operating potential,high capacity,resource availability,and low cost.However,scientific and technological challenges still exist to prepare hard carbon with a high initial Coulombic efficiency(ICE),an excellent rate capability,and good cycling stability.In this work,we report a self-supported hard carbon electrode from fungus-pretreated basswood with an improved graphitization degree and a low tortuosity.Compared with the hard carbon derived from basswood,the hard carbon electrode from fungus-pretreated basswood has an improved rate capability of 242.3 mAh·g^(−1)at 200 mA·g^(−1)and cycling stability with 93.9%of its capacity retention after 200 cycles at 40 mA·g^(−1),as well as the increased ICE from 84.3%to 88.2%.Additionally,ex-situ X-ray diffraction indicates that Na+adsorption caused the sloping capacity,whereas Na+intercalation between interlayer spacing corresponded to the low potential plateau capacity.This work provides a new perspective for the preparation of high-performance hard carbon and gains the in-depth understanding of Na storage mechanism.展开更多
基金supported by the National Key Research and Development Program of China(No.2021YFA2400400)the National Natural Science Foundation of China(Nos.22109058,22122902,22075299,and 21975091)+3 种基金the Fundamental Research Funds for the Central Universities of China(No.20230614)the Jiangxi Provincial Education Department(No.GJJ200338)the Open Fund of Fujian Provincial Engineering Technology Research Center of Solar Energy Conversion and Energy Storage(No.SECES2003)Beijing Natural Science Foundation(No.2222089).
文摘Hard carbon derived from biomass is regarded as a promising anode material for sodium-ion batteries(SIBs)because of its low operating potential,high capacity,resource availability,and low cost.However,scientific and technological challenges still exist to prepare hard carbon with a high initial Coulombic efficiency(ICE),an excellent rate capability,and good cycling stability.In this work,we report a self-supported hard carbon electrode from fungus-pretreated basswood with an improved graphitization degree and a low tortuosity.Compared with the hard carbon derived from basswood,the hard carbon electrode from fungus-pretreated basswood has an improved rate capability of 242.3 mAh·g^(−1)at 200 mA·g^(−1)and cycling stability with 93.9%of its capacity retention after 200 cycles at 40 mA·g^(−1),as well as the increased ICE from 84.3%to 88.2%.Additionally,ex-situ X-ray diffraction indicates that Na+adsorption caused the sloping capacity,whereas Na+intercalation between interlayer spacing corresponded to the low potential plateau capacity.This work provides a new perspective for the preparation of high-performance hard carbon and gains the in-depth understanding of Na storage mechanism.
