Study On Molybdenum Disulfide/Graphene Oxide Nanocomposites Synthesis (Methods And Hydrogen Evolution Properties)

Hummers'method is used to generate the graphite oxide.The MoS₂/GO composites were prepared by hydrothermal method and water bath method,respectively.MoS₂/GO composites decorated with trace loads of Pt exhibits excellent catalytic activity for HER.Introduction of trace loads of Pt nanoparticles as well as the interaction between Pt and GO contribute to enhancement of HER.Moreover,the well-matching layered structure between 2D MoS₂ and graphite oxide not only increase the contact area for efficient charge transfer across the interface,but also exhibits better synergistic effects between two components,thereby greatly improving the electrochemical performances for HER.The main research results are as follows:The few-layer MoS₂/GO composites could be prepared through the hydrothermal reaction between Na₂MoO₄.2H₂O and CH₄N₂S in the presence of graphene oxide sheets.The observed Tafel slope of MoS₂/GO is 136mVdec^-1.Due to the analogous microstructure and morphology between graphene and MoS₂,graphene oxide with superior electrical conductivity,large surface area has been confirmed to be an ideal candidate for preparation of MoS₂/GO.This indicates that the effective loading of MoS₂ on graphene sheets does not only promote the rapid migration of electrons in materials,but also provides a large number of attachment sites and improves catalytic performance.Then chloroplatinic acid was added and MoS₂/RGO/Pt was synthesized by oil bath.After annealing,the crystallinity of the hybrid nanoscale was significantly increased,and the slope of Tafel MoS₂/GO/Pt is 124mVdec^-1,with a smaller impedance than MoS₂/GO.The MoS₂/GO composites could be prepared through the water bath synthesis between?NH₄?₂MoS₄·2H₂O and N₂H₄ in the presence of graphene oxide sheets.When MoS₂ and GO mole ratio is 1:2,MoS₂/GO composites have more defects and active sites and exhibits better synergistic effects between two components,then greatly improving the electrochemical performances for HER.The Tafel slope of MoS₂/GO prepared through the water bath is 68.4mVdec^-1.The slope of Tafel MoS₂/GO/Pt is 47.2mVdec^-1.It was found that the performance of MoS₂/GO composites prepared by water bath method is better than of prepared by hydrothermal reaction method by the results of Tafel curves.Through XRD and SEM,it can be seen that the method of hydrothermal often produces defects such as oxide impurities,which makes the performance unstable.So,hydrothermal method has great potential prospect besides the preparation method is simple.