Controllable Growth of Semiconductor Heterostructures Mediated by Bifunctional Ag2S Nanocrystals as Catalyst or Source-Host

State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Journal of the American Chemical Society (Impact Factor: 11.44). 01/2011; 133(1):148-57. DOI: 10.1021/ja1090996
Source: PubMed

ABSTRACT We demonstrate that Ag(2)S nanocrystals are the bifunctional mediator for controllable growth of semiconductor heterostructures including more complicated multisegments heterostructures in solution-phase, which is a new type of nanomediator and quite different from the metal nanoparticle catalyst. The intrinsic high Ag(+) ion mobility makes Ag(2)S nanocrystals not only exhibit excellent catalytic function for growth of metal sulfide heterostructures but also act as a source-host for growth of ternary semiconductor heterostructures, for example, Ag(2)S-AgInS(2). The semiconductors grow epitaxially from or inward in Ag(2)S nanocrystals forming single-crystalline heterostructures. Moreover, the method developed here also can construct multisegments heterostructures, for example, Ag(2)S-CdS-ZnS, AgInS(2)-Ag(2)S-AgInS(2). The interfacial structure is still stable even if the lattice mismatch is quite large, which is a unique feature of this method.

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