Composition controlled synthesis of Bi rich Bi1−xSbx alloy nanocrystals by a low temperature polyol process

Bi1−xSbxnanocrystals were prepared by a low temperature polyol synthesis process using PVP as a complexing agent as well as a capping agent in controlling crystal growth. This method allows for the preparation of phase pure, highly crystalline nanocrystals of 30–40 nm in diameter in large yield. The structural properties of the nanocrystals were investigated by X-ray diffraction and electron microscopy. Differential thermal analysis of the Bi1−xSbx compositions revealed a single endothermic peak at a lower melting point than that of the bulk. A formation mechanism for the Bi1−xSbx alloy nanocrystals is proposed. The results are discussed in terms of understanding the structural properties of these nanocrystals and introducing a new approach for the bottom-up synthesis of these thermoelectric materials with nano-scale domains.