-
摘要: 采用高溫固相法成功制備了Li2x?ySr1?xTi1?yNbyO3 (x=3y/4, y=0.25, 0.5, 0.6, 0.7, 0.75, 0.8)鋰離子固體電解質,并通過X射線衍射(XRD)、掃描電子顯微鏡(SEM)、交流阻抗圖譜、恒電位極化等分別研究了各個組分的晶體結構、微觀形貌、離子電導率和電子電導率。XRD顯示當y≤0.70時,材料為立方鈣鈦礦型結構,幾乎沒有雜質相生成。SEM表明隨著摻雜含量的增加材料的晶粒尺寸逐漸增大。Li0.35Sr0.475Ti0.3Nb0.7O3鋰離子固體電解質有著高離子電導率,為3.62×10?5 S·cm?1,其電子電導率為2.55×10?9 S·cm?1,活化能僅為0.29 eV。使用以Li0.35Sr0.475Ti0.3Nb0.7O3為隔膜的LiFePO4/Li半電池經過100圈循環后,放電比容量仍有93.9 mA·h·g?1,容量保持率為90.72%。Abstract: All-solid-state lithium batteries are recognized as the next-generation energy storage batteries due to their high energy density and high security, to which researchers have paid more attention. All-solid-state lithium batteries are composed of solid materials, and the Li-ion solid electrolytes do not contain flammable and explosive organic solvents, which can enhance the safety of the battery. As important components, Li-ion solid electrolytes are widely studied in all-solid-state lithium batteries, which currently include Li-superionic solid electrolyte (LISICON), Na-superionic solid electrolyte (NASICON), garnet-type solid electrolyte, perovskite-type solid electrolyte, sulfide-type solid electrolyte, and polymer solid electrolyte. Li-ion solid electrolytes generally have the advantages of high Li-ion conductivity, low electronic conductivity, wide operating temperatures, wide electrochemical windows, and inhibition of lithium dendrite growth. Among the solid electrolytes, the perovskite-type solid electrolytes have a wide tolerance factor that allows most elements to dope into the ABO3 structure. Additionally, the perovskite-type Li-ion solid electrolytes are summarized into two types: (1) the three-component Li3xLa2/3?xTiO3 (LLTO, 0 < x < 1/6) and (2) the four-component (Li, Sr)(A, B)O3 (A = Zr, Hf, Ti, Sn; B = Nb, Ta). In this paper, the four-component Li2x?ySr1?xTi1?yNbyO3 (x = 3y/4, y = 0.25, 0.5, 0.6, 0.7, 0.75, 0.8) solid electrolytes were prepared by conventional solid-state reaction method. X-ray diffraction (XRD), scanning electron microscopy, alternating current impedance, and potentiostatic polarization methods were adopted to study the crystal structure, micromorphology, ion conductivity, and electronic conductivity, respectively. XRD analysis show the synthesized samples exhibit a cubic perovskite structure when y≤0.70 with almost no impurity phase formed. Li0.35Sr0.475Ti0.3Nb0.7O3 exhibits the highest ion conductivity of 3.62×10?5 S·cm?1, electronic conductivity of 2.55×10?9 S·cm?1 at 20 ℃, and activation energy of only 0.29 eV. The LiFePO4/Li half-cell was fabricated using Li0.35Sr0.475Ti0.3Nb0.7O3 as a separator, exhibiting a capacity of 93.9 mA·h·g?1 and a retention capacity of 90.72% after 100 cycles.
-
Key words:
- perovskite /
- Li-ion solid electrolyte /
- AC impedance /
- electronic conductivity /
- lithium battery
-
表 1 Li2x?ySr1?xTi1?yNbyO3 (x=3y/4, y=0.25, 0.5, 0.6, 0.7)的晶胞精修數據
Table 1. Crystal refinement data of Li2x?ySr1?xTi1?yNbyO3 (x = 3y/4, y = 0.25, 0.5, 0.6, 0.7)
Sample Lattice
constant/
nmUnweighted-
profile R
factor /%Weighted
profile R
factor/%Goodness
of fitLi0.125Sr0.8125Ti0.75Nb0.25O3 0.39163 7.351 9.748 7.634 Li0.25Sr0.625Ti0.5Nb0.5O3 0.39315 6.291 8.229 3.709 Li0.3Sr0.55Ti0.4Nb0.6O3 0.39371 6.540 8.963 10.897 Li0.35Sr0.475Ti0.3Nb0.7O3 0.39422 6.354 8.648 9.334 www.77susu.com -
參考文獻
[1] Takada K. Progress and prospective of solid-state lithium batteries. Acta Mater, 2013, 61(3): 759 doi: 10.1016/j.actamat.2012.10.034 [2] Sun C W, Liu J, Gong Y D, et al. Recent advances in all-solid-state rechargeable lithium batteries. Nano Energy, 2017, 33: 363 doi: 10.1016/j.nanoen.2017.01.028 [3] Zheng F, Kotobuki M, Song S F, et al. Review on solid electrolytes for all-solid-state lithium-ion batteries. J Power Sources, 2018, 389: 198 doi: 10.1016/j.jpowsour.2018.04.022 [4] Wang C H, Yang Y F, Liu X J, et. al. Suppression of lithium dendrite formation by using LAGP-PEO (LiTFSI) composite solid electrolyte and lithium metal anode modified by PEO (LiTFSI) in all-solid-state lithium batteries. ACS Appl Mater Inter, 2017, 9: 13694 doi: 10.1021/acsami.7b00336 [5] Adnan S B R S, Salleh F M, Mohamed N S. Effect of interstitial Li+ ion and vacant site Li+ ion on the properties of novel Li2.05ZnAl0.05Si0.95O4 and Li1.95Zn0.95Cr0.05SiO4 ceramic electrolytes. Ceram Int, 2016, 42(15): 17941 doi: 10.1016/j.ceramint.2016.08.047 [6] Hallopeau L, Bregiroux D, Rousse G, et al. Microwave-assisted reactive sintering and lithium ion conductivity of Li1.3Al0.3Ti1.7(PO4)3 solid electrolyte. J Power Sources, 2018, 378: 48 doi: 10.1016/j.jpowsour.2017.12.021 [7] Kokal I, Ramanujachary K V, Notten P H L, et al. Sol-gel synthesis and lithium ion conduction properties of garnet-type Li6BaLa2Ta2O12. Mater Res Bull, 2012, 47(8): 1932 doi: 10.1016/j.materresbull.2012.04.032 [8] Belous A G. Lithium ion conductors based on the perovskite La23?xLi3xTiO3. J Eur Ceram Soc, 2001, 21(10-11): 1797 doi: 10.1016/S0955-2219(01)00118-2 [9] Chen C H, Amine K. Ionic conductivity, lithium insertion and extraction of lanthanum lithium titanate. Solid State Ionics, 2001, 144(1-2): 51 doi: 10.1016/S0167-2738(01)00884-0 [10] Mitsuishi K, Ohnishi T, Tanaka Y, et al. Nazca Lines by La ordering in La2/3–xLi3xTiO3 ion-conductive perovskite. Appl Phys Lett, 2012, 101(7): 073903 doi: 10.1063/1.4744886 [11] Yu R, Du Q X, Zou B K, et al. Synthesis and characterization of perovskite-type (Li, Sr)(Zr, Nb)O3 quaternary solid electrolyte for all-solid-state batteries. J Power Sources, 2016, 306: 623 doi: 10.1016/j.jpowsour.2015.12.065 [12] Chen C H, Xie S, Sperling E, et al. Stable lithium-ion conducting perovskite lithium-strontium-tantalum-zirconium-oxide system. Solid State Ionics, 2004, 167(3-4): 263 doi: 10.1016/j.ssi.2004.01.008 [13] Kong Y Z, Li Y, Lu J Y, et al. Conductivity and electrochemical stability of perovskite-structured lithium-strontium-niobium-hafnium-oxide solid Li-ion conductors. J Mater Sci:Mater Electron, 2017, 28(12): 8621 doi: 10.1007/s10854-017-6586-2 [14] Huang B, Xu B Y, Li Y T, et al. Li-ion conduction and stability of perovskite Li3/8Sr7/16Hf1/4Ta3/4O3. ACS Appl Mater Interfaces, 2016, 8(23): 14552 doi: 10.1021/acsami.6b03070 [15] Kong Y Z, Li Y, Li J W, et al. Li ion conduction of perovskite Li0.375Sr0.4375Ti0.25Ta0.75O3 and related compounds. Ceram Int, 2018, 44(4): 3947 doi: 10.1016/j.ceramint.2017.11.186 [16] Kong Y Z, Li Y, Lu J Y, et al. Effect of doping (Al, La, Sm) on the conductivity of Li0.375Sr0.4375Hf0.25Ta0.75O3 ceramics. Mater Res Express, 2017, 4(9): 095504 doi: 10.1088/2053-1591/aa8ba7 [17] Lu J Y, Li Y. Conductivity and stability of Li3/8Sr7/16?3x/2LaxZr1/4Ta3/4O3 superionic solid electrolytes. Electrochimica Acta, 2018, 282: 409 doi: 10.1016/j.electacta.2018.06.085 [18] Mo S S, Lu P H, Ding F, et al. High-temperature performance of all-solid-state battery assembled with 95(0.7Li2S-0.3P2S5)-5Li3PO4 glass electrolyte. Solid State Ionics, 2016, 296: 37 doi: 10.1016/j.ssi.2016.09.002 [19] Cheng S, Smith D M, Li C Y. Anisotropic ion transport in a poly(ethylene oxide)-LiClO4 solid state electrolyte templated by graphene oxide. Macromolecules, 2015, 48(13): 4503 doi: 10.1021/acs.macromol.5b00972 [20] Lu D L, Ma J M, Wu J L, et al. Preparation and electrochemical properties of Li0.33SrxLa0.56?2/3xTiO3? based solid-state ionic supercapacitor. Ceram Int, 2019, 45(2): 2584 doi: 10.1016/j.ceramint.2018.10.192 [21] Sotomayor M E, Várez A, Bucheli W, et al. Structural characterisation and Li conductivity of Li1/2?xSr2xLa1/2?xTiO3 (0< x< 0.5) perovskites. Ceram Int, 2013, 39(8): 9619 doi: 10.1016/j.ceramint.2013.05.083 [22] Teranishi T, Kouchi A, Hayashi H, et al. Dependence of the conductivity of polycrystalline Li0.33BaxLa0.56-2/3xTiO3 on Ba loading. Solid State Ionics, 2014, 263: 33 doi: 10.1016/j.ssi.2014.05.001 [23] Wei Q, Cui W, Long X, et al. A investigation on the surface state of La1?xMx CoO3(M-Ca, Sr) perovskite oxides by XPS. Chem Res Chin Univ, 1990, 11(11): 1227 doi: 10.3321/j.issn:0251-0790.1990.11.013魏詮, 崔巍, 龍驤, 等. La(1?x)MxCoO3(M=Ca, Sr)表面狀態的XPS研究. 高等學校化學學報, 1990, 11(11):1227 doi: 10.3321/j.issn:0251-0790.1990.11.013 [24] Yu K, Jin L, Li Y, et al. Structure and conductivity of perovskite Li0.355La0.35Sr0.3Ti0.995M0.005O3 (M = Al, Co and In) ceramics. Ceram Int, 2019, 45(18): 23941 doi: 10.1016/j.ceramint.2019.08.012 [25] Ofoegbuna T, Darapaneni P, Sahu S, et al. Stabilizing the B-site oxidation state in ABO3 perovskite nanoparticles. Nanoscale, 2019, 11(30): 14303 doi: 10.1039/C9NR04155A -