CAJ | 학술논문

以商业化V2O5粉体和H2O2为原料，采用溶胶?凝胶法制备了V2O5凝胶，将V2O5凝胶稀释后进行冷冻干燥得到V2O5前驱体，最后在空气中450℃煅烧2 h得到正交晶系的V2O5样品。经过X射线衍射(XRD)、热重分析(TGA)和场发射电子扫描电镜(FESEM)分析发现，V2O5前驱体是具有2D片状结构的V2O5·nH2O粉体，煅烧后转变为2D片状结构的正交晶系V2O5粉体。采用循环伏安(CV)、电化学交流阻抗(EIS)和充放电测试研究了V2O5样品的 Li+扩散系数、电化学反应阻抗、倍率性能和电化学循环稳定性，发现 V2O5样品的 Li+扩散系数和电化学反应阻抗大小与其放电深度密切相关，所制备的2D片状V2O5样品具有较好的倍率性能和优异的电化学循环稳定性。
이상업화V2O5분체화H2O2위원료，채용용효?응효법제비료V2O5응효，장V2O5응효희석후진행냉동간조득도V2O5전구체，최후재공기중450℃단소2 h득도정교정계적V2O5양품。경과X사선연사(XRD)、열중분석(TGA)화장발사전자소묘전경(FESEM)분석발현，V2O5전구체시구유2D편상결구적V2O5·nH2O분체，단소후전변위2D편상결구적정교정계V2O5분체。채용순배복안(CV)、전화학교류조항(EIS)화충방전측시연구료V2O5양품적 Li+확산계수、전화학반응조항、배솔성능화전화학순배은정성，발현 V2O5양품적 Li+확산계수화전화학반응조항대소여기방전심도밀절상관，소제비적2D편상V2O5양품구유교호적배솔성능화우이적전화학순배은정성。
V2O5 gel was prepared by sol-gel method with commercial V2O5 powders and H2O2 as raw materials. Then the V2O5 gel was diluted and freeze-dried to obtain V2O5 precursor. The V2O5 precursor was further treated at 450 °C in air for 2 h to obtain orthorhombic V2O5 sample. X-ray diffraction (XRD), thermogravimetric analysis (TGA), and field emission scanning electron microscope (FESEM) analysis reveal that the precursor is V2O5·nH2O powders with 2D sheet structure, and after calcining in air the V2O5·nH2O powders change into 2D orthorhombic V2O5 powders. Cyclic voltammograms (CV), electrochemical impedance spectroscopy (EIS), and charge-discharge tests were performed to study lithium ion diffusion coefficient, electrochemical reaction impedance, rate performance, and electrochemical cycling stability of the V2O5 sample. The results show that the lithium ion diffusion coefficient and electrochemical reaction impedance are closely related to depth of discharge of the V2O5 sample. The prepared 2D V2O5 sample has good rate performance and excellent electrochemical cycling stability.