Bulk synthesis of long nanotubes of transition metal chalcogenides

Abstract

Nanotubes of transition metal chalcogenides as long as 0.2-20 microns or more, perfect in shape and of high crystallinity, are synthesized from a transition metal material, e.g., the transition metal itself or a substance comprising a transition metal such as an oxide, water vapor and a H 2 X gas or H 2 gas and X vapor, wherein X is S, Se or Te, by a two-step or three-step method. The transition metal chalcogenide is preferably WS 2 or WSe 2 . Tips for scanning probe microscopy can be prepared from said long transition metal chalcogenide nanotubes.

1 . A method for preparation of a tip for scanning probe microscopy comprising attaching to said tip a transition metal chalcogenide nanotube having a length of greater than 0.5 microns.  
     
     
         2 . A method in accordance with  claim 1 , wherein the length of said transition metal chalcogenide nanotube is up to about 20 microns.  
     
     
         3 . A method in accordance with  claim 1 , wherein the length of said transition metal chalcogenide nanotube is at least 1 micron.  
     
     
         4 . A method in accordance with  claim 1 , wherein the length of said transition metal chalcogenide nanotube is 1-20 microns.  
     
     
         5 . A method in accordance with  claim 1 , wherein the length of said transition metal chalcogenide nanotube is 10-20 microns.  
     
     
         6 . A method in accordance with  claim 1 , wherein the said transition metal chalcogenide is WS 2 .  
     
     
         7 . A method in accordance with  claim 1 , wherein the said transition metal chalcogenide is WSe 2 .  
     
     
         8 . A method in accordance with  claim 1 , wherein the said transition metal chalcogenide is MoS 2 .  
     
     
         9 . A method in accordance with  claim 1 , wherein the said transition metal chalcogenide is MoSe 2 .  
     
     
         10 . A tip for scanning probe microscopy having attached thereto a transition metal chalcogenide nanotube having a length of greater than 0.5 microns.  
     
     
         11 . A tip in accordance with  claim 10 , wherein the length of said transition metal chalcogenide nanotube is up to about 20 microns.  
     
     
         12 . A tip in accordance with  claim 10 , wherein the length of said transition metal chalcogenide nanotube is at least 1 micron.  
     
     
         13 . A tip in accordance with  claim 10 , wherein the length of said transition metal chalcogenide nanotube is 1-20 microns.  
     
     
         14 . A tip in accordance with  claim 10 , wherein the length of said transition metal chalcogenide nanotube is 10-20 microns.  
     
     
         15 . A tip in accordance with  claim 10 , wherein the said transition metal chalcogenide is WS 2 .  
     
     
         16 . A tip in accordance with  claim 10 , wherein the said transition metal chalcogenide is WSe 2 .  
     
     
         17 . A tip in accordance with  claim 10 , wherein the said transition metal chalcogenide is MoS 2 .  
     
     
         18 . A tip in accordance with  claim 10 , wherein the said transition metal chalcogenide is MoSe 2 .