以商业二氧化钛(P25)和LiOH分别作为钛源和锂源,采用两步水热和进一步煅烧法制备具有分级结构的钛酸锂(LTO)材料,通过改变煅烧温度调控材料初级颗粒的尺寸,采用X射线衍射、扫描电镜以及恒流充放电等方法对所制备LTO材料微观结构和电化学性能进行研究。结果表明:所制备LTO材料具有分级结构,煅烧温度为600℃时所制LTO600的纯度高且初级颗粒尺寸较小,因此表现出优异的倍率和循环性能,其在1C、5C、10C、20C、30C、40C和50C下的比容量分别为148mAh/g、141mAh/g、136mAh/g、133mAh/g、131mAh/g、129mAh/g和126mAh/g,当电流密度达到60C时,其比容量仍高达123mAh/g,同时,其在10C、20C和50C下经500次循环后,容量保持率分别为90.0%、90.1%和88.1%。
Spinel lithium titanate (LTO) with "zero strain" have attracted much attention owing to their stable charge-discharge platform,excellent cycle performances,low cost and friendly environmental.LTO materials with hierarchical structure were prepared by two-step hydrothermal and further calcination method.During the preparation,commercial titanium dioxide and lithium hydroxide were used as titanium and lithium sources,respectively.The microstructure and electrochemical performances of the as-prepared LTO were characterized by X-ray diffraction,scanning electron microscopy and galvanostatic charge-discharge measurement.The results shown that the obtained LTO samples had hierarchical structure.LTO600 obtained at 600℃ had high purity and small primary particles,and exhibited excellent high-rate and cyclic performances.The specific capacities of LTO600 at 1C,5C,10C,20C,30C,40C and 50C were 148mAh/g,141mAh/g,136mAh/g,133mAh/g,131mAh/g,129mAh/g and 126mAh/g,respectively.Even at 60C,the specific capacity was still as high as 123mAh/g.Moreover,the capacity retention after 500 cycles at 10C,20C and 50C reached 90.0%,90.1% and 88.1%,respectively.
[1] Zhang F,Yi F,Gao A,et al.Interfacial electrostatic self-assembly in water-in-oil microemulsion assisted synthesis of Li4Ti5O12/Graphene for lithium-ion-batteries[J].Journal of Alloys and Compounds,2020,819:153018.
[2] Xiang Y,Zhang W,Chen B,et al.Nano-Li4Ti5O12 particles in-situ deposited on compact holey-graphene framework for high volumetric power capability of lithium ion battery anode[J].Journal of Power Sources,2020,447:227372.
[3] Zhou H H,Ma Q,Yang W,et al.Li4Ti5O12-TiO2 composite coated on carbon foam as anode material for lithium ion capacitors:evaluation of rate performance and self-discharge[J].Chemnanomat,2020,6(2):280-284.
[4] Zhao X C,Yang P,Ding T,et al.Hydrothermally synthesized Li4Ti5O12 nanotubes anode material with enhanced Li-ion battery performances[J].Journal of Nanoscience and Nanotechnology,2019,19(11):7387-7391.
[5] Xie Y B,Gao R R.Electrochemical capacitance of titanium nitride modified lithium titanate nanotube array[J].Journal of Alloys and Compounds,2017,725:1-13.
[6] Huang F F,Ma J M,Xia H Y,et al.Capacity loss mechanism of the Li4Ti5O12 microsphere anode of lithium-ion batteries at high temperature and rate cycling conditions[J].ACS Applied Materials & Interfaces,2019,11(40):37357-37364.
[7] Zhao S,Zhang M M,Xian X C,et al.Insight into the formation mechanism of Li4Ti5O12 microspheres obtained by a CTAB-assisted synthetic method and their electrochemical performances[J].Journal of Materials Chemistry A,2017,5(26):13740-13747.
[8] Liu Y,Yan X D,Xu B Q,et al.Li4Ti5O12 nanosheets assembled in tubular architecture for lithium storage[J].Chemical Engineering Journal,2019,361:1371-1380.
[9] Li J Q,Zhang T F,Han C P,et al.Crystallized lithium titanate nanosheets prepared via spark plasma sintering for ultra-high rate lithium ion batteries[J].Journal of Materials Chemistry A,2019,7(2):455-460.
[10] Kim S D,Rana K,Ahn J H.Additive-free synthesis of Li4Ti5O12 nanowire arrays on freestanding ultrathin graphite as a hybrid anode for flexible lithium ion batteries[J].Journal of Materials Chemistry A,2016,4(48):19197-19206.
[11] Shen L F,Uchaker E,Zhang X G,et al.Hydrogenated Li4Ti5O12 nanowire arrays for high rate lithium ion batteries[J].Advanced Materials,2012,24(48):6502-6506.
[12] Gangaja B,Nair S,Santhanagopalan D.Surface-engineered Li4Ti5O12 nanostructures for high-power Li-ion batteries[J].Nano-Micro Letters,2020,12(1):30.
[13] Liu Y,Yue L P,Lou P,et al.Liquid metal modified Li4Ti5O12 with improved conductivity as novel anode material for lithium-ion batteries[J].Materials Letters,2020,258:126803.
[14] Roh H K,Lee G W,Haghighat-Shishavan S,et al.Polyol-mediated carbon-coated Li4Ti5O12 nanoparticle/graphene composites with long-term cycling stability for lithium and sodium ion storages[J].Chemical Engineering Journal,2020,385:123984.
[15] Xiang Y,Zhang W F,Chen B,et al.Nano-Li4Ti5O12 particles in-situ deposited on compact holey-graphene framework for high volumetric power capability of lithium ion battery anode[J].Journal of Power Sources,2020,447:227372.
[16] Pu Z,Lan Q,Li Y,et al.Preparation of W-doped hierarchical porous Li4Ti5O12/brookite nanocomposites for high rate lithium ion batteries at -20℃[J].Journal of Power Sources,2019,437:226890.
[17] Li D,Liu Y,Zhao W,et al.Synthesis of Ce modified Li4Ti5O12 using biomass as carbon source[J].Journal of Electroanalytical Chemistry,2019,851:113441.
[18] Kim J B,Lee S G,Cho S Y,et al.Doping behavior of Br in Li4Ti5O12 anode materials and their electrochemical performance for Li-ion batteries[J].Ceramics International,2019,45(14):17574-17579.
[19] Tsai P C,Nasara R N,Shen Y C,et al.Ab initio phase stability and electronic conductivity of the doped-Li4Ti5O12 anode for Li-ion batteries[J].Acta Materialia,2019,175:196-205.
[20] Li Y A,Chen Q L,Meng Q Q,et al.One-step synthesis of a nanosized cubic Li2TiO3-coated Br,C,and N Co-doped Li4Ti5O12 anode material for stable high-rate lithium-ion batteries[J].ACS Applied Materials & Interfaces,2019,11(29):25804-25816.
[21] Lee K C,Chang-Jian C W,Ho B C,et al.Conductive PProDOT-Me-2-capped Li4Ti5O12 microspheres with an optimized Ti3+/Ti4+ ratio for enhanced and rapid lithium-ion storage[J].Ceramics International,2019,45(12):15252-15261.
[22] Yao Z J,Yin H Y,Zhou L M,et al.Ti3+ Self-doped Li4Ti5O12 anchored on N-doped carbon nanofiber arrays for ultrafast lithium-ion storage[J].Small,2019,15(50):1905296.
[23] 王媛,邵丹,李向峰,等.低温水热法制备花状球形钛酸锂的性能[J].电池,2018,48(1):25-28.
[24] He Y,Muhetaer A,Li J,et al.Ultrathin Li4Ti5O12 nanosheet based hierarchical microspheres for high-rate and long-cycle life Li-ion batteries[J].Advanced Energy Materials,2017,7(21):1700950.
[25] Zhao S,Ka O,Xian X,et al.Effect of primary crystallite size on the high-rate performance of Li4Ti5O12 microspheres[J].Electrochimica Acta,2016,206:17-25.
[26] Wang Y,Zhou A,Dai X,et al.Solid-state synthesis of submicron-sized Li4Ti5O12/Li2TiO3 composites with rich grain boundaries for lithium ion batteries[J].Journal of Power Sources,2014,266:114-120.
[27] Zhao S,Zhang M,Wang Z,et al.Enhanced high-rate performance of Li4Ti5O12 microspheres/multiwalled carbon nanotubes composites prepared by electrostatic self-assembly[J].Electrochimica Acta,2018,276:73-80.
基金资助
重庆市技术创新与应用示范专项重点示范项目(cstc2018jszx-cyzdX0087);重庆基础与前沿研究计划项目(cstc2016jcyjA0462);中央高校基本科研业务费(2019CDXYHG0013)
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