Molybdenum Disulfide Coating Grow On The Surface Of Metals

Molybdenum disulfide (MoS₂) has been applied in many fields because of itsexcellent capabilities. But MoS₂ easily separate from the substrate of metal. As aresult the treatment technologies on the surface of metals by MoS₂ have attractedmuch attention in recent years. In this paper, it is studied a simple and low costmethod which cheaper thick coating layer can be obtained. Preliminarily researchthe process equipment and parameter of the heat decomposition method toproduce MoS₂ on the substrate of metal.Molybdenum trisulfide (MoS₃) particles were firstly obtained by acidifyingthe mixed solution of sodium sulfide (Na₂S) and sodium molybdate (Na₂MoO₄).Then MoS₂ particles were produced by the desulphurization of the prepared MoS₃which has been coated on the substrate of aluminium, stainless steel, iron, yellowbrass and red copper under N₂ atmosphere.In the first-step reaction, an optimized preparation factor was found aftersingle-factor experiments. The results of characterization by X-ray diffraction(XRD) showed that was amorphous MoS₃ was generated by acidifying the mixedsolution of Na₂S and Na₂MoO₄ with hydrochloric acid (HC1). We can find the bestcondition is: temperature 63℃,C_H+=1.0 mol·L^-1, Na₂S 0.0077 mol; Na₂MoS₄0.001mol, the output of MoS₃ is 94.72%.Thermodynamic analyses demonstrated the feasibility of the second-stepreaction. Proper temperature ranges for the preparation of MoS₂ was found in thisprocess. The crystallization and temperature of the decomposition of MoS₂prepared under different conditions were investigated by XRD and differentialthermal-thermogravimetric analysis (DTA/TGA). The resules showed that thereaction temperature was the primary factor, that affect status of crystallization, size of particles and decomposition of MoS₃.The combination status of MoS₂ coated on the substrate of aluminium,stainless steel, iron, yellow brass and red copper were investigated by scanningelectronic microscope (SEM) and energy spectrum analysis (EDS). The resultsshowed that the reaction temperature and different backing metal were theprimary factors.