Formation of Heteroepitaxy in Different Shapes of Au–CdSe Metal–Semiconductor Hybrid Nanostructures

Abstract

Formation of heteroepitaxy and designing different-shaped heterostructured nanomaterials of metal and semiconductor in solution remains a frontier area of research. However, it is evident that the synthesis of such materials is not straightforward and needs a selective approach to retain both metal and semiconductor identities in the reaction system during heterostructure formation. Herein, the epitaxial growth of semiconductor CdSe on selected facets of metal Au seeds is reported and different shapes (flower, tetrapod, and core/shell) hetero-nanostructures are designed. These results are achieved by controlling the reaction parameters, and by changing the sequence and timing for introduction of different reactant precursors. Direct evidence of the formation of heteroepitaxy between {111} facets of Au and (0001) of wurtzite CdSe is observed during the formation of these three heterostructures. The mechanism of the evolution of these hetero-nanostructures and formation of their heteroepitaxy with the planes having minimum lattice mismatch are also discussed. This shape-control growth mechanism in hetero-nanostructures should be helpful to provide more information for establishing the fundamental study of heteroepitaxial growth for designing new nanomaterials. Such metal-semiconductor nanostructures may have great potential for nonlinear optical properties, in photovoltaic devices, and as chemical sensors.

Nonepitaxial Gold‐Tipped ZnSe Hybrid Nanorods for Efficient Photocatalytic Hydrogen Production

“…This finding is different from the reports of Pradhan and co-workers that the formation of the heteroepitaxial junction of the (111) facet of cubic Au on the (111) facet of wormlike zinc blend ZnSe nanocrystals, as well as the epitaxial growth of the (111) facet of gold along the [002] direction of the CdSe NRs. [37,47] In both cases, Au precursor was injected into the presynthesized zinc blende ZnSe or wurtzite CdSe nanocrystals at a high temperature of ≈190 °C and grew at 250 °C. Another work by Manna and co-workers [17,19] reveals that annealing of nonepitaxial Au-CdS nanocrystals prepared by wet-chemical synthetic approaches results in the formation of epitaxial Au-CdS hybrid nanocrystals.…”

Synthesis and Biomedical Applications of Multifunctional Nanoparticles

“…On the other hand, FePt–CdS and FePt–CdSe heterodimers are formed from metallic seed NPs in the presence of chalcogen and cadmium precursors . Besides, the {111} plane of face‐centered cubic metals has a structural resemblance to hexagonal arrangement of S and Se atoms on the wurtzite {001} plane of CdS and CdSe, which is called as coincidence site lattices . Due to this resemblance in addition to the chemical affinity, the interface energy between metal and semiconductor phases can be further reduced.…”

New Gold Nanostructures for Sensor Applications: A Review

“…GNWs with defined geometry are fabricated by electron beam lithography through selective removal of either the exposed or non-exposed regions [67,68,69,70]. With the development of electrodeposition, lithographically patterned nanowire electrodeposition (LPNE) can produce polycrystalline GNWs through a sacrificial nickel nanoband electrode and recess a horizontal trench into a defined thickness of GNWs [58].…”