OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible.

Electrochemically stable molybdenum disulfide (MoS₂) with a two-dimensional nanowall structure is successfully prepared by a simple two-step synthesis method followed by thermal annealing at 700 °C in a reducing atmosphere. MoS₂ nanowalls provide a better electrochemical performance and stability when cellulose (CMC) binder is used instead of the usual PVDF. The electrodes exhibit a high specific discharge capacity of 880 mA h g⁻¹ at 100 mA g⁻¹ without any capacity fading for over 50 cycles. The electrode also exhibits outstanding rate capability with a reversible capacity as high as 737 mA h g⁻¹ and 676 mA h g⁻¹ at rates of 500 mA g⁻¹ and 1000 mA g⁻¹ at 20 °C, respectively. The excellent electrochemical stability and high specific capacity of the nano structured materials are attributed to the two-dimensional nanowall morphology of MoS₂ and the use of cellulose binder. These results are the first of its kind to report a superior stability using bare MoS₂ as an active material and CMC as a binder.

Three dimensional (3D) MoS2 nanoflowers are successfully synthesized by hydrothermal method. Further, a composite of as prepared MoS2 nanoflowers and rGO is constructed by simple ultrasonic exfoliation technique. The crystallography and morphological studies have been carried out by XRD, FE-SEM, TEM, HR-TEM and EDS etc. Here, XRD study revealed, a composite of exfoliated MoS2 with expanded spacing of (002) crystal plane and rGO can be prepared by simple 40 minute of ultrasonic treatment. While, FE-SEM and TEM studies depict, individual MoS2 nanoflowers with an average diameter of 200 nm are uniformly distributed throughout the rGO surface. When tested as sodium-ion batteries anode material by applying two different potential windows, the composite demonstrates a high reversible specific capacity of 575 mAhg−1 at 100 mAg−1 in between 0.01 V–2.6 V and 218 mAhg−1 at 50 mAg−1 when discharged in a potential range of 0.4 V–2.6 V. As per our concern, the results are one of the best obtained as compared to the earlier published one on MoS2 based SIB anode material and more importantly this material shows such an excellent reversible Na-storage capacity and good cycling stability without addition of any expensive additive stabilizer, like fluoroethylene carbonate (FEC), in comparison to those in current literature.

No abstract

No abstract