Fast microwave-assisted synthesis of Li-stuffed garnets and insights into Li diffusion from muon spin spectroscopy
Fast microwave-assisted synthesis of Li-stuffed garnets and insights into Li diffusion from muon spin spectroscopy
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DOI：
10.1039/c5ta08107f
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发表时间：
2016-01-01
影响因子：
11.9
通讯作者：
Corr, Serena A.
中科院分区：
文献类型：
--
作者：
Amores, Marco;Ashton, Thomas E.;Corr, Serena A.
锂填充石榴石由于其作为锂电池固态电解质的突出潜力而引起了巨大的关注。然而，在这些复杂功能氧化物的可靠合成中存在持续的挑战，并且缺乏对这些重要材料中锂离子扩散机制的完整理解。解决这些问题对于实现石榴石材料作为电解质在所有固态锂离子电池中的应用至关重要。在这项工作中，一个立方相石榴石的名义组成Li6.5Al0.25La2.92Zr2O12是通过微波辅助的固态路线合成的第一次，大大减少了反应时间和加热温度。通过电化学阻抗谱（EIS）和最先进的μ子自旋弛豫（mSR）谱研究锂离子扩散行为，分别显示活化能为0.55 +/- 0.03 eV和0.19 +/- 0.01 eV。这种差异源于高的晶粒间电阻，这有助于EIS测量中的总电阻。相比之下，mSR充当局部探针，提供对晶格顺序的洞察，给出锂扩散系数的估计值为4.62 x 10（-11）cm（2）s（-1）。这些结果证明了这种锂填充石榴石作为全固态锂离子电池的固态电解质的潜力，这是储能界越来越感兴趣的领域。
Lithium-stuffed garnets attract huge attention due to their outstanding potential as solid-state electrolytes for lithium batteries. However, there exists a persistent challenge in the reliable synthesis of these complex functional oxides together with a lack of complete understanding of the lithium-ion diffusion mechanisms in these important materials. Addressing these issues is critical to realizing the application of garnet materials as electrolytes in all solid-state lithium-ion batteries. In this work, a cubic phase garnet of nominal composition Li6.5Al0.25La2.92Zr2O12 is synthesized through a microwave-assisted solid-state route for the first time, reducing considerably the reaction times and heating temperatures. Lithium-ion diffusion behavior is investigated by electrochemical impedance spectroscopy (EIS) and state-of-art muon spin relaxation (mSR) spectroscopy, displaying activation energies of 0.55 +/- 0.03 eV and 0.19 +/- 0.01 eV respectively. This difference arises from the high inter-grain resistance, which contributes to the total resistance in EIS measurements. In contrast, mSR acts as a local probe providing insights on the order of the lattice, giving an estimated value of 4.62 x 10(-11) cm(2) s(-1) for the lithium diffusion coefficient. These results demonstrate the potential of this lithium-stuffed garnet as a solid-state electrolyte for all-solid state lithium-ion batteries, an area of growing interest in the energy storage community.