Quantitative detection of microscopic lithium distributions with neutrons

The importance of lithium in the modern industrial society is continuously increasing. Spatially resolved detection of tritium particles from ⁶Li(n,α)³H nuclear reactions is used to reconstruct microscopic lithium distributions. Samples are exposed to a flux of cold neutrons. Emitted charged particles are detected with a PSD. Introducing a pinhole aperture between target and detector, the experimental setup works like a “camera obscura”, allowing to perform spatially resolved measurements. Tritium detection analysis was successfully used to reconstruct the lithium content in self-organized TiO_2-x-C and Si/TiO_2-x-C nanotubes electrochemically lithiated, for the first time. Titanium dioxide nanotubes are a candidate for a safe anode material in lithium-ion batteries. Also lithium distributions in geological samples, so called “pathfinder-minerals” containing lithium, like lepidolite from a pegmatite, were analyzed. With this development we present a new precision method using nuclear physics for material science.
Supported by the DFG (GE 2296/1-1).