We demonstrate a facile way to alleviate lithium polysulfide shuttle effect by using aluminum phosphate (AlPO₄) as a bifunctional additive in lithium-sulfur (Li-S) batteries. AlPO₄ microparticles are synthesized via sol-gel and subsequent calcination process. The effects of AlPO₄ on adsorption of lithium polysulfide as well as the performance of Li-S cell are investigated. The Li-S cell containing AlPO₄ 1.0 wt% retains 76% of the initial capacity after 100 cycles at 0.2 C and it retains 453 mAh∙g⁻¹ at 1.0 C. Using ex-situ X-ray photoelectron spectroscopy and infra-red analysis, it is found that lithium polysulide is chemically adsorbed on AlPO₄ through Lewis acid-base interaction with the PO groups in (PO₄)^3-. The improvement in cycling stability is attributed to the strong interaction between AlPO₄ and lithium polysulfides. The adsorbed lithium polysulfides are converted to thiosulfates/polythionates, preventing the dissolution of the lithium polysulfides into the electrolyte and migration to the anode. Various electrochemical measurements including electrochemical impedance spectroscopy and cyclic voltammetry demonstrate that AlPO₄ lowers the interfacial resistance and helps fast reversible conversion reaction of sulfur to lithium polysulfides, which enables fast charge/discharge. These results suggest that use of AlPO₄ is a convenient and effective way to improve the performance of Li-S batteries.

我们展示了一种通过使用磷酸铝（AlPO ₄）作为锂硫（Li-S）电池中的双功能添加剂来减轻多硫化锂穿梭效应的简便方法。通过溶胶-凝胶和随后的煅烧过程合成AlPO ₄微粒。研究了AlPO ₄对多硫化锂的吸附以及Li-S电池性能的影响。含有1.0 wt％AlPO ₄的Li-S电池在0.2 C循环100次后保留初始容量的76％， 在1.0 C保留453 mAh∙g ^-1。使用异位X射线光电子能谱和红外光谱分析发现，多硫化锂化学吸附在AlPO _4上通过路易斯酸碱与（PO ₄）^3-中的P O基相互作用。循环稳定性的提高归因于AlPO ₄和多硫化锂之间的强相互作用。吸附的多硫化锂被转化为硫代硫酸盐/多硫代酸盐，从而防止了多硫化锂溶解到电解质中并迁移到阳极。各种电化学测量（包括电化学阻抗谱和循环伏安法）表明，AlPO ₄降低了界面电阻，并有助于硫向多硫化锂的快速可逆转化反应，从而实现快速充电/放电。这些结果表明使用AlPO ₄ 是提高Li-S电池性能的便捷有效途径。