Na0.44MnO2–CNT electrodes for non-aqueous sodium batteries

Crystalline Na0.44MnO2 materials are readily synthesized via a solid state method followed by mixing with carbon nanotubes (CNTs). The obtained Na0.44MnO2–CNT composites consist of rod-like Na0.44MnO2 particles entangled with CNTs. Their electrochemical properties were thoroughly investigated in assembled non-aqueous Na0.44MnO2–CNT//Na cells using cyclic voltammetry, galvanostatic testing, and electrochemical impedance spectroscopy. The results show that the Na0.44MnO2–CNT material can deliver a high capacity over 113 mAh g−1 with stable cycling performance over 40 cycles. In addition, it exhibits an excellent rate capability, delivering a capacity of 95 mAh g−1 at a high rate of 5 C. The high capacity retention combined with remarkable high-rate capability makes Na0.44MnO2–CNT a promising electrode material for advanced Na-ion batteries.