Catalytic and catalyst-free synthesis of CdSe nanostructures with single-source molecular precursor and related device application.

Air-stable single-source molecular precursor is applied for controlled size and morphology synthesis of one-dimensional and quasi-one-dimensional CdSe nanostructures. Two different growth approaches are compared to control the growth of nanostructures. When combined with well-defined Au colloidal catalysts, the use of single-source molecular precursor allows diameter control synthesis of monodispersed CdSe nanowires from 10-30 nm via a vapor-liquid-solid mechanism. In addition, a variety of CdSe nanostructures with different morphologies can be achieved and tuned without assistance of metallic catalysts by carefully manipulating dynamic thermal decomposition process of single-source molecular precursor. The new level of synthetic control afforded by our present work opens up new opportunities for using as-synthesized CdSe nanostructures as model systems for fundamental studies as well as building blocks for larger scale functional device assembly. Importantly, we demonstrate that a single CdSe tripod can be natively configured as a nanoscale phototransistor in which photocurrent created between two tripod arms can be efficiently modulated by applying a gate voltage through the third arm.