Project Details
Projekt
Functionalization of MoS2 and WS2 sulfide nanotubes: From controlled synthesis to organized assembly and function
Applicant
Professor Dr. Wolfgang Tremel
Subject Area
Experimental Condensed Matter Physics
Term
from 2006 to 2010
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 26108932
ObjectivesThis project deals with the functionalization of chalcogenide nanotubes with organic and polymer ligands in order to(i) tailor the solubilities of chalcogenide nanotubes in various polar or unpolar solvents and/or to integrate them into inorganic/polymer hybrid structures,(ii) to bind photoexcitable or redoxactive ligands (e.g. metalloporphyrins for light harvesting) to the sidewalls of the tubes,(in) to attach nanoparticles such as metal (Au, Ag), semiconductor (ZnS, CdSe) particles to the sidewall of the tubes,(iv) to fabricate thin films from MoSa nanotubes on oxidic or ceramic surfaces and to produce layer-by-layer assembled composites from MoS2 and/or WS2 nanotubes and poiyelectrolytes,(v) attach ligands to the surface in order to build up organized assemblies of chalcogenide nanotubes.The proposed research will focus on MoS2 and WS2 nanotubes, which are available in sufficient amounts and quality.Methods and plan of operationThe functionalization strategy is based on tripod or tetrapod ligands which are bonded to the outer surface layer of the chalcogenide tube by transition metals (Ni2+ or Co2+) which act as a glue for the attachment of the ligand. The multiped ligand carries a linker group for the attachment of other functional molecules or nanoparticles and a spacer group for adjusting the separation between the nanotube and the particles or molecules attached. The multipod ligand can be attached as a sidegroup to the backbone of a block copolymer, where the second side group carries the functional ligands are acts as an anchor group for metal or semiconductor particles. The advantage of the polymer ligand approach is that the nanotube/ligand complex do not rely on the stability of a single bond but rather on multifunctional docking. The validity of this approach has been demonstrated with nitrilotriacetic acid (NTA) on fullerene-type MoSz nanoparticles.Significance of the proposed researchSuccessful performance of this research will provide a general methodology for a designed chemical modification of chalcogenide nanoparticles, which are of special interest for their lubricating and s hock-absorbing (MoS2, WSn) and electronic properties (NbS2, NbSe2).
DFG Programme
Priority Programmes
