Depth Distribution of Lithium in Oxidized Binary Al-Li Alloys Determined by Secondary Ion Mass Spectrometry and Neutron Depth Profiling

Application of high-spatial-resolution secondary ion mass spectrometry for nanoscale chemical mapping of lithium in an Al-Li alloy

“…The characterisation of lithium (Li) has received considerable attention from multiple disciplines in materials science in particular researchers working on the development of Li-ion battery materials and high-strength, low-density Al-Li alloys [1][2][3][4][5][6][7][8][9] . High-spatialresolution chemical mapping of Li is of particular interest in the case of Li-ion battery materials for investigating Li ion transport on the electrodes with nanoscale structures 1,8,9 .…”

“…High-spatialresolution chemical mapping of Li is of particular interest in the case of Li-ion battery materials for investigating Li ion transport on the electrodes with nanoscale structures 1,8,9 . It also offers excellent potential for revealing the distribution of nanoscale Li-rich precipitates in Al-Li alloys to understand their influence on mechanical and corrosion performance [4][5][6][7] . However, the analysis of Li is challenging as many techniques, such as energy dispersive X-ray spectroscopy (EDX or EDS) and X-ray photoelectron spectroscopy (XPS), have low elemental sensitivity for Li and/or insufficient spatial resolution 3,10 .…”

“…This technique offers excellent potential for obtaining statistically meaningful information with a very high elemental sensitivity of Li, as it is an electropositive element with a high ionisation probability. However, the application of SIMS instruments is typically limited to a lateral resolution of ~ 1 μm [1][2][3][4][5][6][7] , which is insufficient for revealing the details of Li distribution at the nanoscale.…”

“…3 For instance, researchers using the NanoSIMS 50L (Cameca, France), using a Cs + primary ion beam with an impact energy of 16 keV and a lateral resolution of ~ 100 nm, were able to perform nanoscale analysis of Li in LiCoO2-based battery cathode materials by mapping 7 Li 16 Oto investigate the elemental distribution and the change of surface chemistry during electrochemical cycling 8 . A recently-developed compact design of time-of-flight (ToF) SIMS analyser (TOFWERK, Switzerland) added to a focused ion beam-scanning electron microscope (FIB-SEM) was also used to resolve the segregation of Li on grain boundaries and interfaces of particles in the LiNixMnyCo1-x-yO2 cathodes with a lateral resolution of ~ 50 nm 9,16 .…”

“…A recently-developed compact design of time-of-flight (ToF) SIMS analyser (TOFWERK, Switzerland) added to a focused ion beam-scanning electron microscope (FIB-SEM) was also used to resolve the segregation of Li on grain boundaries and interfaces of particles in the LiNixMnyCo1-x-yO2 cathodes with a lateral resolution of ~ 50 nm 9,16 . The use of a Zeiss ORION NanoFab Helium/Neon ion microscope equipped with a 25 keV He + primary ion source and a magnetic mass spectrometer has achieved a lateral resolution of 10 nm by mapping 7 Li + in a lithium titanate and magnesium oxide nanoparticle mixture 17,18 .…”