Spontaneous Formation of Wurzite-CdS/Zinc Blende-CdTe Heterodimers through a Partial Anion Exchange Reaction

Abstract

Ion exchange of ionic semiconductor nanoparticles (NPs) is a facile method for the synthesis of type-II semiconductor heterostructured NPs with staggered alignment of band edges for photoelectric applications. Through consideration of the crystallographic orientation and strain at the heterointerface, well-designed heterostructures can be constructed through ion exchange reactions. Here we report the selective synthesis of anisotropically phase-segregated cadmium sulfide (CdS)/ cadmium telluride (CdTe) heterodimers via a novel anion exchange reaction of CdS NPs with an organic telluride precursor. The wurtzite-CdS/zinc blende-CdTe heterodimers in this study resulted from spontaneous phase segregation induced by the differences in the crystal structures of the two phases, accompanying a centrosymmetry breaking of the spherical CdS NPs. The CdS/CdTe heterodimers exhibited photoinduced spatial charge separation because of their staggered band-edge alignment.

Facile formation of Ag2WO4/AgX (X=Cl, Br, I) hybrid nanorods with enhanced visible-light-driven photoelectrochemical properties

“…As an excellent photocatalyst for water and air purification, one-dimensional (1D) semiconductor nanostrucutures, including nanowires, nanorods, nanotubes, and nanobelts, etc., have demonstrated significantly enhanced catalytic efficiency because of their high aspect ratio, enhanced light scattering, and absorption, rapid transport of free electron along the long axis, and efficient utilization of electronhole pair [4][5][6][7][8][9]. Distinct from their single component counterparts, semiconductor hybrid nanostructures with a staggered alignment of band edges at the hetero-interface can improve spatial charge separation of the electron and hole in different parts of the heterostructure for photocatalytic and photovoltaic applications [10][11][12][13][14][15][16]. To take advantage of both materials, the fabrication of 1D semiconductor hetero-nanostructures with controllable shape and size is extremely important from the viewpoints of both fundamental research and technical applications.…”

A transferable force field for CdS-CdSe-PbS-PbSe solid systems

“…20,23 In the IE process, either the cations or anions in a nanostructure are partially or completely replaced by a substitutional ion from a solution or vapor. 21,22 OA and IE can be independently used [24][25][26][27][28][29][30][31] or combined 32 to synthesize nanostructures such as nanowires, nanorod couples, dimers, thin films, and 2-D superlattices. They are promising techniques in the design and application of nanomaterials and nanodevices.…”

Lead Halide Perovskite Nanocrystals in the Research Spotlight: Stability and Defect Tolerance

“…Anion sublattice bonding is rather stronger than that of the cation sublattice, while the anions themselves are often bulkier than the cations, making anion exchange difficult without using extreme conditions, and usually any exchange that is observed is not topotaxial. 83,84 …”