Molybdenum‐Incorporated O3‐type Sodium Layered Oxide Cathodes for High‐Performance Sodium‐Ion Batteries

• Published in: Energy technology (Weinheim, Germany) Germany), 2023-12, Vol.11 (12), p.n/a
• Main Authors: Moossa, Buzaina, Abraham, Jeffin James, Gayara, Ranasinghe Arachchige Harindi, Ahmed, Abdul Moiz, Shahzad, Rana Faisal, Kahraman, Ramazan, Al-Qaradawi, Siham, Rasul, Shahid, Shakoor, Rana Abdul
• Format: Article
• Language: English
• Subjects: cathode materials; Cathodes; Electrochemical analysis; Electrochemical impedance spectroscopy; Electrochemistry; Electrode materials; energy storage; Irregular particles; layered oxide battery materials; Manganese; Molybdenum; Particle shape; Sodium; Sodium-ion batteries; Solid electrolytes; solid-state; Structural analysis; Thermal stability; Transition metals
• ISSN: 2194-4288; 2194-4296
• DOI: 10.1002/ente.202300437

Transition metal layered oxide materials with a general formula NaxMO2 (M = Ni, Mn, Co, Fe) are widely researched with various possible electrode configurations. Herein, O3‐type NaNi(1−x)/2Mn(1−x)/2MoxO2 (x = 0, 0.05,0.1) layered oxide cathode materials are synthesized by solid‐state reaction method, and its structural, thermal, and electrochemical performance in sodium ion battery is investigated. The structural analysis reveals that a single phase highly crystalline O3‐type cathode material with an irregular particle shape is formed. The introduction of molybdenum improves the thermal stability of cathode materials, which can be attributed to the improved TMO2 layers that provide stability to the material. The addition of Mo to Na‐layered oxide cathode materials enhances electrochemical performance. The developed cathode materials, the NaNi0.475Mn0.475Mo0.05O2, exhibit excellent specific discharge capacity (≈154 mAh g−1) at C/20 rate, (an increase of ≈20% when compared to the NaNi0.5Mn0.5O2) which can be attributed to the increased capacitance effect by the addition of Mo. The electrochemical impedance spectroscopy study reveals that the diffusion of Na+ into/from the host structure is rapid during the first cycle and then gradually reduces with subsequent cycling due to the formation of the solid electrolyte interface layer, which hinders Na+ migration. This has a potential effect on the improved electrochemical performance of the material. The work presents an O3‐type Na‐layered oxide material incorporating molybdenum. A facile, green solid state method results in the synthesis of the Mo‐containing NaNi(1−x)/2Mn(1−x)/2MoxO2 (x = 0, 0.05, 0.1) material. Structural characterizations confirm the phase of pure synthesis. The Mo‐0.05 gives the best electrochemical performance with an achieved specific discharge capacity of ≈154 mAhg−1.