摘要
采用水基流变相辅助的固相法,以异质碳蔗糖和石墨为碳源,合成了LiMn_(0.8)Fe_(0.2)PO_(4)/C复合材料,研究了不同石墨加入方式对所制复合材料电化学性能的影响,并对所制备的LiMn_(0.8)Fe_(0.2)PO_(4)/C复合材料进行了X射线衍射(XRD)、N_(2)吸附-脱附测试、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等表征。结果表明,不同石墨包覆工艺对材料结构和电化学性能具有显著影响。前驱体煅烧后再加入石墨获得的样品纯度高,形貌呈均一的椭圆形,在0.1C下的放电比容量为149 mAh·g^(-1),达到其理论比容量的87%;在5C下最大的放电比容量为133 mAh·g^(-1);在2C倍率下经过300次循环后比容量维持在127 mAh·g^(-1),衰减率仅为1.9%,表现出了优良的循环稳定性。
LiMn_(0.8)Fe_(0.2)PO_(4)/C composite was synthesized using sucrose and graphite as heterogeneous carbon sources through a solid-state method assisted by aqueous rheological phase.The effect of different addition methods of graphite on electrochemical performances was studied.The LiMn_(0.8)Fe_(0.2)PO_(4)/C composite was characterized by the X-ray diffraction(XRD),N_(2) adsorption-desorption,scanning electron microscopy(SEM),and transmission electron microscopy(TEM).The results showed that different graphite coating processes had obvious effects on the structure and electrochemical properties of the materials.The sample,which the graphite was added after the precursor was calcined,showed a high purity and uniform elliptic morphology.And its specific discharge capacity was 149 mAh·g^(-1)(87%of the theoretical specific capacity)at 0.1C.The specific discharge capacity was 133 mAh·g^(-1) at 5C.After 300 cycles at 2C,its capacity was maintained at 127 mAh·g^(-1),whose decay rate was 1.9%,showing excellent electrochemical performances.
作者
李元超
黄卫峰
梁鹏超
赵子芳
邢保艳
闫东亮
杨理
王松林
LI Yuanchao;HUANG Weifeng;LIANG Pengchao;ZHAO Zifang;XING Baoyan;YAN Dongliang;YANG Li;WANG Songlin(School of Chemistry and Chemical Engineering,Henan Institute of Science and Technology,Xinxiang,Henan 453003,China;Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education),Nankai University,Tianjin 300071,China)
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2024年第4期751-760,共10页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金(No.22309044)
河南省高校科技创新人才计划(No.23HASTIT014)
河南省重点研发与推广专项(科技攻关)(No.222102240001)资助。
