Solid state synthesis of layered sodium manganese oxide for sodium-ion battery by in-situ high energy X-ray diffraction and X-ray absorption near edge spectroscopy
Multi intermediate phases including P3 and P′3 was observed before O′3 phase NaMnO2 can be formed at 600 °C. Residue sodium carbonate doesn't have any obvious negative effect on sodium cathode. P2 type Na2/3MnO2 synthesized at 600 °C have low initial charge capacity.