Facile One-Step Synthesis and Transformation of Cu(I)-Doped Zinc Sulfide Nanocrystals to Cu_1.94S–ZnS Heterostructured Nanocrystals

Abstract

A facile one-pot heating process without any injection has been developed to synthesize different Cu-Zn-S-based nanocrystals. The composition of the products evolves from Cu(I)-doped ZnS (ZnS:Cu(I)) nanocrystals into heterostructured nanocrystals consisting of monoclinic Cu1.94S and wurtzite ZnS just by controlling the molar ratios of zinc acetylacetonate (Zn(acac)2) to copper acetylacetonate (Cu(acac)2) in the mixture of n-dodecanethiol (DDT) and 1-octadecene (ODE). Accompanying the composition transformation, the crystal phase of ZnS is changed from cubic zinc blende to hexagonal wurtzite. Depending on the synthetic parameters including the reaction time, temperature, and the feeding ratios of Zn/Cu precursors, the morphology of the as-obtained heterostructured nanocrystals can be controlled in the forms of taper-like, matchstick-like, tadpole-like, or rod-like. Interestingly, when the molar ratio of Cu(acac)2 to Zn(acac)2 is increased to 9:1, the crystal phase of the products is transformed from monoclinic Cu1.94S to the mixed phase composed of cubic Cu1.8S and tetragonal Cu1.81S as the reaction time is further prolonged. The crystal-phase transformation results in the morphological change from quasi-spherical to rice shape due to the incorporation of Zn ions into the Cu1.94S matrix. This method provides a simple but highly reproducible approach for synthesis of Cu(I)-doped nanocrystals and heterostructured nanocrystals, which are potentially useful in the fabrication of optoelectronic devices.

Electrodeposited semiconductors at room temperature: an X-ray Absorption Spectroscopy study of Cu-, Zn-, S-bearing thin films

“…According to these authors, approaching room temperature no ternary compounds are found, while only binary mixtures between ZnS and the numerous phases of the Cu-S and Cu-Zn binary diagrams exist. In spite of this lack of miscibility between the three constituents [27][28], proposed the mixtures of binary terms as novel materials for optoelectronic devices, especially if in nanometric dimension. Accordingly, the aims of this study include the verification of the possible occurrence of a ternary film with E-ALD.…”

Colloidal Copper Sulphide Based Nanocrystals as Building Blocks for Self-assembled Nanostructures

“…For instance, copper sulphide-cadmium sulphide hetero-nanostructures, which have a type II band alignment, facilitating the separation of light induced charge carriers, are interesting candidates for nanostructured solar cells [50]. Similar properties are also expected for PbS or the less toxic ZnS, attached to copper sulphide nanoparticles [21,24,[51][52][53][54]. The presence of ZnS or MnS can strongly influence the position of the plasmon band of copper sulphide particles.…”

Thermochemistry of the E-ALD process for the growth of CuxZnyS on Ag(111): Interpretation of experimental data

“…As far as we know, there are few attempts to synthesize mixed Cu-Zn sulphide compounds [27][28][29][30][31][32][33][34] . Uhuegbu et al claimed to have synthesized Cu-Zn-S compounds through a one-pot synthesis with metal chlorides and thiourea in solution, assisted by opportune complexing agents 27 .…”