Abstract
以Mn（CH3COO）2·4H2O为锰源,以Na2CO3为钠源,通过溶液-凝胶法合成干凝胶前驱体,将前驱体在空气气氛中焙烧得到Na-Mn-O正极材料.并用傅立叶红外光谱（FT-IR）,热重分析（TG）,X射线衍射（XRD）,扫描电镜（SEM）,恒流充放电测试等对材料结构和性能进行研究.结果表明,600℃焙烧的样品为结构稳定的层状锰酸钠,属于六方层状P2结构,空间群为P63/mmc,通过PowderX软件计算得到其晶胞参数为a=0.284nm,c=1.116nm.Na-Mn-O正极材料在Li^＋嵌入和脱出过程中,部分Na^＋从层状主晶格中脱出,使得Li^＋在MnO6层间的嵌/脱阻力减小（由于Na^＋（0.095nm）半径比Li^＋（0.076nm）大）,电化学性能明显改善.在充放电电流密度为25mA·g^-1,电压在2.0-4.3V范围时,600℃焙烧的样品第二次放电容量高达176mAh·g^-1,20次循环后,容量保持率仍有90.9%.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
