Fig. 2: The structural transitions of P2-Na0.67TmO2 upon air-exposure.
From: The stability of P2-layered sodium transition metal oxides in ambient atmospheres
The XRD patterns of a Na0.67MnO2 and b Na0.67Ni0.33Mn0.67O2 samples exposed in different atmosphere. c The refinement results of exposed Na0.67MnO2 and Na0.67Ni0.33Mn0.67O2 samples with a two-phase model. The SEM images of d pristine and e RH 93% + CO2 exposed Na0.67MnO2 powder, f The EDS mapping results of exposed Na0.67MnO2, indicating that NaHCO3 is formed on the particles’ surface. The SEM images of g pristine and h RH 93% + CO2 exposed Na0.67Ni0.33Mn0.67O2 powder. i The EDS mapping results of RH 93% + CO2 exposed Na0.67Ni0.33Mn0.67O2 samples, NaHCO3 particles are also observed on the surface of exposed Na0.67Ni0.33Mn0.67O2. The exposure time of the above samples are 3 days.
