Solution-Phase Synthesis of Layered Transition Metal Dichalcogenide Nanoparticles
A method of synthesizing two-dimensional (2D) nanoparticles of transition metal dichalcogenide (TMDC) material utilises a molecular cluster compound. The method allows a high degree of control over the shape, size and composition of the 2D TMDC nanoparticles, and may be used to produce material with uniform properties in large quantities.
1 . A two-dimensional nanoflake comprising:
a molecular cluster compound; and
a core semiconductor material disposed on the molecular cluster compound.
2 . The two-dimensional nanoflake of claim 1 , wherein the core semiconductor material comprises an element of the transition metals and an element of Group 16 of the periodic table.
3 . The two-dimensional nanoflake of claim 2 , wherein the element of the transition metals is selected from the group consisting of Mo and W.
4 . The two-dimensional nanoflake of claim 2 , wherein the element of Group 16 comprises O, S, Se or Te.
5 . The two-dimensional nanoflake of claim 1 , wherein the two-dimensional nanoflake is a two-dimensional quantum dot.
6 . The two-dimensional nanoflake of claim 1 , wherein the two-dimensional nanoflake is a single-layered quantum dot.
7 . The two-dimensional nanoflake of claim 1 further comprising a shell of a second semiconductor material disposed on the core semiconductor material.
8 . The two-dimensional nanoflake of claim 1 , wherein the core semiconductor material comprises one or more elements not in the molecular cluster compound.
9 . The two-dimensional nanoflake of claim 1 , wherein the molecular cluster compound is [R 3 NR′] 4 [M 10 E 4 (SPh) 16 ] where M=Cd or Zn; E and E′ are independently selected from S and Se; and R and R′ are independently selected from the group consisting of H, Me and Et.
10 . The two-dimensional nanoflake of claim 1 , wherein the two-dimensional nanoflake further comprises an outermost layer comprising a ligand.
11 . The two-dimensional nanoflake of claim 10 , wherein the ligand comprises an alkyl chalcogenide.
12 . The two-dimensional nanoflake of claim 1 , wherein the two-dimensional nanoflake emits light of a second wavelength when irradiated by light of a first wavelength.
13 . A method of producing a two-dimensional nanoflake comprising:
converting a nanoparticle precursor composition to a nanoparticle, wherein said converting is effected in the presence of a molecular cluster, under conditions permitting seeding and growth of the nanoparticle; and
converting the nanoparticle to the two-dimensional nanoflake using a cutting procedure.
14 . The method of claim 13 , wherein the nanoparticle precursor composition comprises:
a first precursor species containing a first ion to be incorporated into the nanoparticle; and
a second precursor species containing a second ion to be incorporated into the nanoparticle.
15 . The method of claim 13 , wherein the nanoparticle precursor composition comprises a single-source precursor.
16 . The method of claim 13 , wherein the two-dimensional nanoflake is a two-dimensional quantum dot.
17 . The method of claim 13 , wherein the two-dimensional nanoflake is a single-layered quantum dot.
18 . The method of claim 13 , wherein the cutting procedure comprises refluxing the nanoparticle in a solvent.
19 . The method of claim 18 , wherein the solvent comprises myristic acid.
20 . The method of claim 13 , wherein the cutting procedure comprises intercalation and exfoliation.