Zhao Wanying, Zhang Ruixue, Li Hongjiao, Zhang Yunsheng, Wang Yao, Wu Chaoling, Yan Yigang, Chen Yungui
College of Materials Science and Engineering, Sichuan University, Chengdu 610065, China.
Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu 610207, China.
ACS Appl Mater Interfaces. 2021 Jul 14;13(27):31635-31641. doi: 10.1021/acsami.1c06164. Epub 2021 Jun 28.
Interfacial engineering is an efficient approach to improve the ionic conductivity of solid-state electrolytes. In the present study, we report the enhancement of formed nanocrystalline LiO on the thermal stability and electrochemical properties of amide lithium borohydride, LiBH·NH ( = 0.67-0.8). LiBH·NH-LiO composites with different amounts of LiO are prepared by a one-step synthesis process by ball milling the mixture of LiBH, LiNH, and LiOH in molar ratios of 1:: ( = 1, 2, 3, 4). Owing to the strong interfacial effect with nanocrystalline LiO, LiBH·NH is converted to the amorphous state in the presence of 78 wt % LiO at = 4. Consequently, the ionic conductivity of LiBH·NH at 20 °C is improved by orders of magnitude up to 5.4 × 10 S cm, the NH desorption temperature is increased by more than 20 °C, and the electrochemical window is widened from 0.5 to 3.8 V.
界面工程是提高固态电解质离子电导率的一种有效方法。在本研究中，我们报道了在酰胺基硼氢化锂LiBH₃·NH₃（x = 0.67 - 0.8）中形成的纳米晶Li₂O对其热稳定性和电化学性能的增强作用。通过球磨LiBH₄、LiNH₂和LiOH的摩尔比为1:x:y（x = 1、2、3、4）的混合物，采用一步合成法制备了具有不同Li₂O含量的LiBH₃·NH₃ - Li₂O复合材料。由于与纳米晶Li₂O的强界面效应，在x = 4且Li₂O含量为78 wt%的情况下，LiBH₃·NH₃转变为非晶态。因此，LiBH₃·NH₃在20℃时的离子电导率提高了几个数量级，达到5.4×10⁻⁵ S cm⁻¹, NH₃脱附温度提高了20℃以上，电化学窗口从0.5 V拓宽到3.8 V。
