Template Preparation And Friction Properties Of Transitional Metal Disulfide Nanotubes

Transition metal dichalcogenides MS₂(M=Mo,W) have attracted considerable interest as excellent solid lubricant.The dangling bonds on the edge of ordinary MS₂ crystal have chemical activity,and to be oxidized easily in ambition,especially in humanity conditions,the friction properties of lubricants decrease.The unique closed MoS₂ and WS₂ nanotubes have eliminated the fringe dangling bonds,thereafter they improves the chemical stability and have very expansive application prospects on tribology.Based on the excellent tribology capability of MS₂ nanotubes,Many experimental approachs to fabricate MS₂ nanotubes have been reported.Although they have extensively studied the reaction mechanisms,they have not been able to control the size or size distribution of the nanotubes,with large range within a single synthesis.In order to settle the problem,In this article,experimental investigation and theoretical analysis were carried out on the preparation process and tribology properties of MS₂ nanostructures in AAO templates with ordered and uniformity nanopores.(1)AAO templates were fabricated in different anodic oxidative conditions by anodic oxidation of aluminum foils,so the pores in AAO(anodic aluminum oxide,AAO) templates might have different diameters,different densities.The effect of anodic oxidative conditions such as voltage and time of pore-large in the as-grown AAO templates were studied intensively.It is possible to prepare AAO template with nano-pore arrays whose qualities can be controlled randomly.(2)The images of AAO were characterized by scanning electron microscope(SEM) and atom force microscope(AFM).The result indicated that the pores in the as-prepared AAO templates owned nearly the same diameter,parallel arrangement and huge density.It is a very excellent basis for template preparation of MS₂ nanotubes.(3) MS₂ nanotubes arrays were prepared using a thermal decomposition of (NH₄)₂MoS₄ and(NH₄)₂WS₄ on anodic aluminum oxide(AAO) template.Then the image,compositon and structure of those products were investigated by SEM, TEM,XRD and EDS,While indicated that the ordered nanotubes arranged with uniform dimension which almost coincided with that of AAO templates.(4) The micro-tribology capability of MS₂ nanotubes were studied.The MS₂ nanomaterial as additives in oil lubrications were tested by UMT-2.The test was carried out in different load,rotated speed and different additives concentration in oil lubrication.(5) The friction mechanism of lubrication including MS₂ as additives was discussed preliminary.The lubrication has excellent tribology proerties may be due to the following factors:MS₂ nanomaterials have unique structures,surface and interface domino offect and size domino offect.