Fig. 4: Comparison of the first cycle discharge energy of various Mn/Fe-based sodium layered oxides.
From: Manipulating O3/P2 phase ratio in bi-phasic sodium layered oxides via ionic radius control
Selected materials contained sufficient Na for reasonable initial coulombic efficiencies, had a high average discharge potential of ca. 3 V or above and good cycling stability of at least 80% retention over at least 50 cycles. Dark red symbols correspond to Ni and/or Co-containing materials, while green symbols demonstrate that a material is Li, Co, and Ni-free. Our example bi-phasic materials are highlighted by green circles16,17,18,19,20,21,22,23,24,25,26,27,28.
