Operando pair distribution function analyses to determine the nature of the oxidized species of oxygen in an O2-type lithium rich layered ox

This proposal aims to study the local structural rearrangements that occur in O2-type lithium-rich layered manganese oxide during the first cycle of lithium electrochemical (de)intercalation. The O2-LiMn0.75O2 phase will be used as the positive electrode material in lithium-metal batteries. Total X-ray scattering intensities will be collected at the ID31 beamline from the O2-LiMn0.75O2 materials operando during the first charge and the discharge of the batteries. Pair distribution functions (PDFs) will then be calculated, which will allow the changes in the first oxygen-oxygen distances during cycling to be precisely monitored. This would help us to identify the nature of the oxidized species of oxygen (oxidized oxide ions O-, peroxo-like ions O22- or trapped O2 gas molecules) during the first charge.