TY - JOUR AB - Two types of MnO2 polymorphs, ?-MnO2 and ?-MnO2 nanorods, have been synthesized by a hydrothermal method. Their crystallographic phases, morphologies, and crystal structures were characterized by XRD, FESEM and TEM analysis. Different exposed crystal planes have been identified by TEM. The electrochemical properties of ?-MnO 2 and ?-MnO2 nanorods as cathode materials in Na-ion batteries were evaluated by galvanostatic charge/discharge testing. Both ?-MnO2 and ?-MnO2 nanorods achieved high initial sodium ion storage capacities of 278 mA h g-1 and 298 mA h g-1, respectively. ?-MnO2 nanorods exhibited a better electrochemical performance such as good rate capability and cyclability than that of ?-MnO2 nanorods, which could be ascribed to a more compact tunnel structure of ?-MnO2 nanorods. Furthermore, the one-dimensional architecture of nanorods could also contribute to facile sodium ion diffusion in the charge and discharge process. © The Royal Society of Chemistry 2013. AU - Su, D AU - Ahn, HJ AU - Wang, G DA - 2013/04/21 DO - 10.1039/c3ta00031a EP - 4850 JO - Journal of Materials Chemistry A PY - 2013/04/21 SP - 4845 TI - Hydrothermal synthesis of ?-MnO2 and ?-MnO 2 nanorods as high capacity cathode materials for sodium ion batteries VL - 1 Y1 - 2013/04/21 Y2 - 2024/03/29 ER -