Colloidal hydrophilic silicon germanium alloy nanocrystals with a high boron and phosphorus concentration shell

Abstract

Si_1−xGe_x alloy nanocrystals potentially have superior properties compared to Si nanocrystals such as an enhanced absorption cross-section and wider controllability of the band gap energy. However, reports on the synthesis of Si_1−xGe_x alloy nanocrystals, especially colloidal Si_1−xGe_x alloy nanocrystals, are still very limited and the quality is not as high as that of colloidal Si nanocrystals. Here, we report the development of a new type of luminescent colloidal Si_1−xGe_x alloy nanocrystals of 3 to 6 nm in diameter. The characteristic feature of the Si_1−xGe_x alloy nanocrystals is the formation of a high B and P concentration layer on the surface. The shell provides inorganic atomic ligands and B and P co-doped Si_1−xGe_x nanocrystals can be dispersed in alcohol without any surface functionalization processes.