In this study, NaAlTi(PO) (NATP) with oxygen vacancies was synthesized using a high-temperature solid-phase method. Then, NATP and polyacrylonitrile (PAN) were combined to form NATP-PAN composite solid-state electrolytes. X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses demonstrated the presence of oxygen defects in NATP. Al doping created oxygen vacancies in NATP, which decreased the activation energy for Li ions transport; this increased the mobility of Li ions in the material, broadening the electrochemical window of the electrolyte. The NaAlTi(PO)-PAN solid-state electrolytes achieved an excellent ionic conductivity of 4.51 × 10 S cm at 20 °C and a wide electrochemical stability window of 5.2 V (vs. Li/Li). NaAlTi(PO)-PAN composite electrolyte was used to assemble a Li||Li symmetric half-cell, which exhibited good interface stability and an overpotential of approximately ±60 mV at a current density of 0.25 mA cm. Furthermore, Li׀NaAlTi(PO)-PAN׀LiFePO was assembled into an all-solid-state lithium metal battery, which exhibited excellent electrochemical performance, with the initial discharge capacity of 255.0 mA h g at 0.1 C. After 100 cycles, the discharge capacity was maintained at 229.6 mA h g, and the capacity retention rate was 90.0 %. Increasing dopant concentration, the oxygen defect concentration is increasing, which plays a crucial role in the ionic conductivity as well as the interface stability.

中文翻译：

---

缺陷工程为全固态锂离子电池构建具有稳定电化学窗口和界面的有机-无机复合电解质


本研究采用高温固相法合成了具有氧空位的NaAlTi(PO) (NATP)。然后，将NATP与聚丙烯腈（PAN）结合形成NATP-PAN复合固态电解质。 X 射线粉末衍射 (XRD) 和 X 射线光电子能谱 (XPS) 分析表明 NATP 中存在氧缺陷。 Al掺杂在NATP中产生氧空位，降低了Li离子传输的活化能；这增加了材料中锂离子的迁移率，拓宽了电解质的电化学窗口。 NaAlTi(PO)-PAN固态电解质在20°C下实现了4.51×10 S cm的优异离子电导率和5.2 V（相对于Li/Li）的宽电化学稳定性窗口。采用NaAlTi(PO)-PAN复合电解质组装Li||Li对称半电池，其表现出良好的界面稳定性，在0.25 mA cm的电流密度下具有约±60 mV的过电势。此外，将Li׀NaAlTi(PO)-PAN׀LiFePO组装成全固态锂金属电池，表现出优异的电化学性能，0.1 C下的首次放电容量为255.0 mAh g-1，经过100次循环后，容量维持在229.6mAh·g，容量保持率为90.0%。增加掺杂剂浓度，氧缺陷浓度增加，这对离子电导率和界面稳定性起着至关重要的作用。