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The Pb-birnessite was prepared by ion exchange from K-birnessite, which was synthesized by calcination of KMnO 4 . Measure methods of SEM (scanning electron microscopy), XRD (X-ray diffraction), TGA (thermogravimetric analyse), AAS (atomic absorption spectrometry), slow-scanning cyclic voltammetry and galvanostatic step discharge/charge are applied. Potentiostatic step method is used for the determination of a chemical diffusion coefficient D is Li +. XRD patterns indicate the Pb-birnessite has layered structure. Slow-scanning voltammograms show the occurrence of a single-phase redox reaction. The galvanostatic discharge/charge curves indicate the Pb-birnessite has better rechargeability at a high discharge/charge rate. Li + can reversibly intercalate into and de-intercalate from the Pb-birnessite during discharge and charge. Pb between the layers stabilized the layered structure and prevented partially the conversion to spinel-like structures. The average value of the chemical diffusion coefficient D of Li + intercalated into the Pb-birnessite is 8.24×10 -11 cm 2 5s -1 .
The Pb-birnessite was prepared by ion exchange from K-birnessite, which was synthesized by calcination of KMnO 4. Measure methods of SEM (scanning electron microscopy), XRD (X-ray diffraction), TGA (thermogravimetric analysis), AAS Potentiostatic step method is used for the determination of a chemical diffusion coefficient D is Li +. Slow-scanning cyclic voltammetry and galvanostatic step discharge / charge are applied. voltammograms show the occurrence of a single-phase redox reaction. The galvanostatic discharge / charge curves indicate the Pb-birnessite has a better rechargeability at a high discharge / charge rate. Li + can reversibly intercalate into and de- intercalate from the Pb-birnessite during discharge and charge. Pb between the layers stabilized the layered structure and prevented partially the conversion to spinel-like structures. The average value of the chemic al diffusion coefficient D of Li + intercalated into the Pb-birnessite is 8.24 × 10 -11 cm 2 5s -1.