The benefits of using GCIBs for depth profiling of inorganic materials is less clear, due to issues of preferential sputtering still remaining and artefacts being introduced. XPS depth profiles have been recorded for GaAs (100) wafers using GCIBs of varying beam energies and cluster sizes to investigate the effects of different GCIB conditions on the preferential sputtering of As and ion beam induced microtopography. GCIB bombardment of GaAs has also been modelled using the molecular dynamics (MD) code to provide an insight into the effects of using different GCIB conditions for XPS depth profiling of compound semiconductors, such as GaAs

Lithium-ion batteries (LIBs) are key to the transition from fossil fuels towards increased use of renewable energy sources, but their cycle-life is limited by degradation processes. We report here detailed ex-situ studies of the interfacial degradation in Ni-rich LiNixMnyCozO2 (NMC) cathode materials cycled vs. graphite. We connect electrochemical signatures of cell degradation with interfacial characterisation with Hard X-ray Photoelectron Spectroscopy (HaXPES), to reveal chemical signatures of different degradation regimes. We then introduce several complementary approaches to performing operando x-ray photoelectron and absorption spectroscopy (XPS/XAS), demonstrating how these can resolve solid-electrolyte interphase (SEI) formation on Li-ion battery anodes.