Facile synthesis, optical properties and growth mechanism of elongated Mn-doped ZnSe1−xSxnanocrystals

Abstract

Transition-metal doping in semiconductors is an important way to modulate their intrinsic properties or bring out new functionalities for applications. Here, elongated Mn-doped ZnSe_1−xS_x nanocrystals are synthesized through a facile one-pot reaction under mild conditions. These ZnSe_1−xS_x nanocrystals with a diameter of 2–4 nm have a cubic phase structure. EPR and PL spectra confirm the successful doping of Mn²⁺ into the ZnSe_1−xS_x nanocrystals, based on the corresponding hyperfine splitting constants and emission bands. The temporal evolution of UV-vis absorption and PL spectra indicates the growth-doping mechanism for the formation of the doped nanocrystals. Surface coating of these nanocrystals with a shell increases the quantum yield up to 35%. And the dual-function role of 1-dodecanethiol is confirmed in the formation of the elongated Mn-doped ZnSe_1−xS_x nanocrystals.