Nano Tungsten Disulfide / Graphene Composite Catalyst

The fuel cell has easily obtained raw materials, high energy density, long service life, cleaning and other advantages, as a new energy efficient conversion system.
 
nano tungsten disulfide / graphene composite catalyst image
 
It has the potential to become one of the micro electronic components of the alternative energy. Electrocatalysis is a key element in fuel cells. Electrocatalysts must have the following characteristics: high electrocatalytic activity, large specific surface area, good electrical conductivity, good stability and proper support.
 
Graphene, as a typical two-dimensional material, has large specific surface area, good flexibility, and very high electron conduction rate. With the discovery of graphene and characterization of transition metal chalcogenides, same as the typical layered structure of compounds such as WS2 exfoliatedinto research on lubricant, lithium battery, photoelectric catalysis, super capacitors and other aspects of the single or few layer structure has also made good progress. In the past, some scholars have tried to use nano-tungsten carbide / graphene composite electrocatalytic methanol fuel cell, and achieved good results. Recently, some scholars have tried to combine graphene with nano-tungsten disulfide with monolayer structure, composition of nano tungsten disulfide / graphene composite catalyst. What about the effect?
 
Layered six dimensional WS2/RGO composites were synthesized by in-situ hydrothermal synthesis on the surface of graphene oxide using tungsten chloride as tungsten source and thioacetamide as sulfur source. The results show that after high-temperature heat treatment, WS2 forms a few layer structure and uniformly adheres to graphene to form a stable two-dimensional composite. Compared with pure WS2 and RGO, the catalytic oxygen reduction activity of the composites was greatly improved because of the synergistic effect between WS2 and RGO, and the defects and active sites of RGO were increased during in situ synthesis, in the process of oxygen reduction, it is beneficial to the dissociation of O2 molecule and the activation energy of the system, which is more conducive to the process of oxygen reduction in the four electron pathway.
 
With more in-depth research on monolayer 2D materials, scientists have found that the nanotite tungsten disulfide / graphene composite catalyst has a corrected starting potential and a limiting current density. It has excellent cycle stability and methanol tolerant performance than pt. Moreover, the process of hydrothermal synthesis of this composite is simple, and the cost of the composite material is lower than that of platinum, and it has good electrocatalytic performance. Therefore, nano-tungsten disulfide / graphene composite catalyst in the field of fuel cells also has the great potential out of the laboratory.
 
 

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