自组装MoS_2纳米结构的可控合成及电催化产氢性能研究

Synthesis of self-assembly MoS_2 nanostrucutres and their applications as electrocatalysts for efficient hydrogen evolution

以廉价的仲钼酸铵和硫化铵为原料合成出硫代钼酸铵[(NH_4)_2Mo S_4]前驱体,通过调控前驱体浓度,采用水热法实现二硫化钼(MoS_2)纳米颗粒、纳米片和纳米花的可控自组装制备,分析其自组装生长机理.研究MoS_2不同纳米结构对电催化产氢性能的影响,发现纳米片结构的MoS_2具有较高的催化活性,析氢过电位仅为310 m V,塔菲尔斜率为32.7m V/dec,并且随着纳米片层数增加,球形纳米花结构的MoS_2催化活性降低,但其催化稳定性较好.

The precursor（ NH_4）_2Mo S_4 was synthesized through cheap raw material of ammonium,molybdate and（ NH_4）_2S solution. Three different morphology molybdenum disulfide（ MoS_2） nanostructures,such as nanoparticles,ultrathin thickness nanosheets and slef- assembly nanoflowers,have been successfully synthesized by a simple solvothermal method with regulating the concentration of（ NH_4）_2Mo S_4 solution. The electrocatalystic performance of three nanostructures were investigated. The results indicated that few layers ultrathin MoS_2 nanosheets showed highest electrocatalyst activity which have low onset potential（ 310 m V） and tafel slope（ 32. 7 m V / dec）. The MoS_2 nanoflows showed the most stability electrocatalyst performance with enhance the layer of nanosheet. In light of high effective surface area and the ability to facilitate good electron transportantion,this unique nanostructure would be favorable for efficient eletricatalytic H_2 evolution from water splitting。