Predicted stable Li(5)P(2)and Li4P at ambient pressure: novel high-performance anodes for lithium-ion batteries
Predicted stable Li(5)P(2)and Li4P at ambient pressure: novel high-performance anodes for lithium-ion batteries
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预测环境压力下稳定的Li(5)P(2)和Li4P：新型高性能锂离子电池负极
DOI：
10.1039/d0cp03297b
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发表时间：
2020
影响因子：
3.3
通讯作者：
Liu Xiaobing
中科院分区：
文献类型：
--
作者：
Fei Ge;Duan Shuai;Zhang Mingxin;Ren Zebin;Cui Yangfan;Chen Xin;Liu Yunxian;Yi Wencai;Liu Xiaobing
富锂磷化物作为锂离子电池的高容量、高倍率阳极材料，近年来引起了人们的广泛关注。然而，由于已知的Li-P化合物的导电性差或体积变化大，迄今为止仍然缺乏有希望的候选者。在这项工作中，我们报告了两个新的Li-P状态，Li 5 P2和Li 4P，在高压下稳定，预测是淬火到环境条件下的第一性原理群结构计算。预测的P3 m1 Li 5 P2显示出有趣的特征，作为p型半导体，具有0.787 eV的间接带隙，在电输运中具有显著的各向异性性质，而Rm Li 4P在0-82 GPa的压力下作为具有金属行为的典型的半导体。更重要的是，我们的计算表明，Li 5 P2和Li 4P的理论容量预计分别达到2164和3462 mA h g−1。结合良好的电输运性质，计算的Li 5 P2的体积膨胀（130%）被发现比以前报道的Li-P化合物小得多，表明其作为LIB的高性能阳极材料的潜力。
Lithium-rich phosphides have recently attracted considerable attention due to their potential application as high-capacity and high-rate anodes for lithium-ion batteries (LIBs). However, there is still short of the promising candidate thus far because of the poor electrical conductivity or huge volume change in the already known Li–P compounds. In this work, we report two novel Li–P states, Li5P2 and Li4P, stabilized under high pressures that are predicted to be quenchable down to ambient conditions by first-principles swarm structure calculations. The predicted P3m1 Li5P2 shows interesting features as a p-type semiconductor with an indirect band gap of 0.787 eV, possessing significant anisotropy properties in electrical transport, while Rm Li4P acts as a typical electride with metallic behavior at pressures of 0–82 GPa. More importantly, our calculations reveal that the theoretical capacities of Li5P2 and Li4P are predicted to reach 2164 and 3462 mA h g−1, respectively. Combined with the good electrical transport properties, the calculated volume expansion of Li5P2 (130%) is found to be much smaller than those of the previously reported Li–P compounds, indicating its potential as a high performance anode material for LIBs.