机构地区:[1]北京化工大学化学工程学院,有机无机复合材料国家重点实验室,化工资源有效利用国家重点实验室,北京100029
出 处:《物理化学学报》2024年第6期44-53,共10页Acta Physico-Chimica Sinica
基 金:国家自然科学基金(52002014,U2003216);广西自然科学基金(2021GXNSFAA220018);深圳市科创项目(CJGJZD20210408092801005)资助。
摘 要:铁硫化物因其较高的理论容量,被认为是一种很有前途的钠离子电池负极材料。然而,铁硫化物在充放电过程中存在较大的体积变化,导致其倍率性能和稳定性较差。本文通过简单的一步法策略,制备了一种具有三维簇状结构的硫掺杂碳包覆的Fe_(0.95)S_(1.05)纳米球(Fe_(0.95)S_(1.05)@SC),并研究了其储钠性能。硫掺杂碳层可提高材料的导电率,缓解Fe_(0.95)S_(1.05)纳米球在反应过程中产生的体积膨胀,故提升了材料的稳定性。Fe_(0.95)S_(1.05)@SC的相互贯通的簇状结构,为电子和离子的传输提供了通道,使材料具备优异的倍率性能。在半电池体系中,Fe_(0.95)S_(1.05)@SC在0.1A·g^(-1)下循环100圈后,保留614.7 m Ah·g^(-1)的高比容量,10 A·g^(-1)下比容量仍可以达到235.7 m Ah·g^(-1)。在全电池体系中,在0.1和10 A·g^(-1)时,Fe_(0.95)S_(1.05)@SC的可逆容量分别为482.8和288.3 m Ah·g^(-1)。该材料具有良好电化学性能,在钠离子电池中具有广阔的应用前景。Sodium-ion batteries(SIBs),featuring with adequate sodium resources,relatively high safety,and similar chemical properties between sodium and lithium,have been considered one of the most potential candidates to lithium-ion batteries(LIBs).However,the larger radii of sodium ions(vs.lithium ions)lead to sluggish diffusion kinetics of sodium ions,low storage capacity,and adverse volume variation during sodiation and desodiation.In particular,anode materials work well in LIBs have been proved ineffective in SIBs.Therefore,the development of cheap anode materials with remarkable performance is critical to the commercialization of SIBs.Despite the good conductivity and robust stability of carbon materials,they usually showcase moderate discharge capacity and poor rate performance in SIBs.Iron sulfides are considered promising anode materials for SIBs due to their high theoretical capacity.Nevertheless,iron sulfides exhibit severe volumetric expansion during charge and discharge,resulting in low rate performance and poor stability.In this regard,hybridizing carbon materials with iron sulfides to configure composite materials is an important way to improve the electrochemical performance of SIBs.Here,three-dimensional clusterstructured sulfur-doped carbon-coated Fe_(0.95)S_(1.05)nanospheres(Fe_(0.95)S_(1.05)@SC)are crafted by one-step annealing of ferrocene and sulfur powder,of which the implementation as anode of sodium ion batteries is reported.Scanning electron microscopy(SEM),transmission electron microscope(TEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)results confirm the successful synthesis of the Fe_(0.95)S_(1.05)@SC composite.The coated sulfur-doped carbon layer can improve the conductivity of the Fe_(0.95)S_(1.05)material and alleviate corresponding volume expansion during the reaction process,thus delivering a robust electrochemical stability.The interconnected cluster structures of Fe_(0.95)S_(1.05)@SC provide channels for the transport of electrons and ions,enabling the material excelle
关 键 词:钠离子电池 负极 硫掺杂碳 Fe_(0.95)S_(1.05)@SC电极
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...