| Abstract
| - A new type of amphiphilic ABC triblock copolymer, poly(acrylic acid)33−poly(styrene)47−poly(ethyleneoxide)113 (PAA33−PS47−PEO113), was designed to assist the synthesis of core/shell structured CdTe nanowiresvia a one-step synthetic route. The PAA block was adopted to capture cadmium ions as the precursor ofCdTe. Due to the bivalent coordination of Cd2+, the copolymer in dioxane/H2O formed micelles with Cd2+−polychelate cores. Then CdTe nanocrystals were obtained within the micelles after introduction of NaHTeinto the micelle solution. Transmission electron microscopy experiments revealed that the CdTe nanocrystalsobtained simultaneously formed “pearl-necklace” aggregates in solution possibly driven by dipole interactionsbetween neighboring particles, and then single crystalline CdTe nanowires upon reflux. Accompanyingthis morphology change, a phase transition from cubic zinc blende to wurtzite structure was observed byselected-area electron diffraction. The aggregation of the PS block in dioxane with a certain amount of H2Oenabled the PS blocks to form a densely packed shell on the CdTe nanowires whose typical size is 700−800nm in length and 15−20 nm in width. The third block of PEO was employed to render the finally formedCdTe nanowires dispersibility.
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