Controllable growth of semiconductor heterostructures mediated by bifunctional Ag2S nanocrystals as catalyst or...

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.