From protonation & Li-rich contamination to grain-boundary segregation: Evaluations of solvent-free vs. wet routes on preparing Li_(7)La_(3)Zr_(2)O_(12) solid electrolyte  

作　　者：Xiao Huang Yang Lu Yajun Niu Jiawen Tang Yongjian Zhou Yan Yang Bingbing Tian 

机构地区：[1]SZU-NUS Collaborative Innovation Center for Optoelectronic Science&Technology,International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education,Institute of Microscale Optoelectronics,Shenzhen University,Shenzhen 518060,Guangdong,China [2]Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology,Department of Chemical Engineering,Tsinghua University,Beijing 100084,China [3]Collaborative Innovation Center for Vessel Pollution Monitoring and Control,Dalian Maritime University,Dalian 116026,Liaoning,China

出　　处：《Journal of Energy Chemistry》2022年第10期223-239,I0005,共18页能源化学（英文版）

基　　金：the financial support from the National Key R&D Project (2018YFE0181300);the National Natural Science Foundation of China (Grant No. 52102284);the China Postdoctoral Science Foundation (2020M682871);the Guangdong Natural Science Funds (2019A1515010675);the Science and Technology Project of Shenzhen (JCYJ20190808142209376 and JCYJ20210324094206019)。

摘　　要：Garnet-type Li_(7)La_(3)Zr_(2)O_(12)(LLZO) has been recognized as a candidate solid electrolyte for high-safety Lianode based solid-state batteries because of its electro-chemical stability against Li-metal and high ionic conductivity. Solvent(e.g., isopropanol(IPA)) has been commonly applied for preparing LLZO powders and ceramics. However, the deterioration of the proton-exchange between LLZO and IPA/absorbed moisture during the mixing and tailoring route has aroused less attention. In this study, a solvent-free dry milling route was developed for preparing the LLZO powders and ceramics. For orthogonal four categories of samples prepared using solvent-free and IPA-assisted routes in the mixing and tailoring processes, the critical evaluation was conducted on the crystallinity, surficial morphology, and contamination of ascalcinated and as-tailored particles, the cross-sectional microstructure of green and sintered pellets,the morphology and electro-chemical properties of grain boundaries in ceramics, as well as the interfacial resistance and performance of Li anode based symmetric batteries. The wet route introduced Li-rich contaminations(e.g., Li OH·H)_(2)O and Li)_(2)CO)_(3)) onto the surfaces of LLZO particles and Li-Ta-O segregations at the adjacent and triangular grain boundaries. The LLZO solid electrolytes prepared through dry mixing in combination with the dry tailoring route without the use of any solvent were found to the optimal performance. The fundamental material properties in the whole LLZO preparation process were found, which are of guiding significance to the development of LLZO powder and ceramic production craft.

关 键 词：Li_(7)La_(3)Zr_(2)O_(12) Solid electrolyte Solvent-free procedure Ion-exchange Grain boundary Fundamental material properties 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ131.11[化学工程—无机化工] TQ174.1