Controlled synthesis of monodispersed AgGaS2 3D nanoflowers and the shape evolution from nanoflowers to colloids

Monodispersed AgGaS2 three-dimensional (3D) nanoflowers have been successfully synthesized in a “soft-chemical” system with the mixture of 1-octyl alcohol and cyclohexane as reaction medium and oleylamine as surfactant. The crystal phase, morphology and chemical composition of the as-prepared products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution TEM (HTEM), respectively. Results reveal that the as-synthesized AgGaS2 nanoflowers are in tetragonal structure with 3D flower-like shape. Controlled experiments demonstrated that the shape transformation of AgGaS2 nanocrystals from 3D nanoflowers (50 nm) to nanoparticles (10–20 nm) could be readily realized by tuning the reaction parameters, e.g., the ratio of octanol to cyclohexane, the length of carbon chain of fatty alcohol, the concentration of oleylamine, etc. The UV–vis and PL spectra of the obtained AgGaS2 nanoflowers and colloids were researched. In addition, the photoelectron energy conversion (SPV) of AgGaS2 nanoflowers was further researched by the surface photovoltage spectra.

Various AgGaS2 nanocrystals with different morphologies and sizes including 3D nanoflowers (a) and colloids (b) were synthesized in mixed solvent reaction system and their PL spectra was researched (c).Figure optionsDownload as PowerPoint slideHighlights
► Ternary chalcogenide AgGaS2 nanocrystals were synthesized in a simple mixed solvent system.
► The shape and size transformation of AgGaS2 from 3D nanoflowers to colloids could be tuned effectively.
► AgGaS2 nanoflowers was obtained with relatively insufficient ligands protection in reaction system, otherwise, AgGaS2 colloids was obtained.
► Provide a new choice to prepare ternary nanomaterials and further understand the reaction mechanisms along with the growth kinetics of ternary nanocrystals.