Chalcogenide glass nanospheres with tunable morphology by liquid-phase template approach.

Chalcogenide glass (ChG) with unique material properties has been widely used in mid-infrared. Traditional ChG microspheres/nanospheres preparation usually uses a high-temperature melting method, in which it is difficult to accurately control the size and the morphology of the nanospheres. Here, we produce nanoscale-uniform (200-500 nm), morphology-tunable, and arrangement-orderly ChG nanospheres from the inverse-opal photonic crystal (IOPC) template by the liquid-phase template (LPT) method. Moreover, we refer to the formation mechanism of nanosphere morphology as the evaporation-driven self-assembly of colloidal dispersion nanodroplets within the immobilized template and find that the concentration of ChG solution and the pore size of IOPC are the key to control the morphology of the nanospheres. The LPT method is also applied to the two-dimensional microstructure/nanostructure. This work provides an efficient and low-cost strategy for the preparation of multisize ChG nanospheres with tunable morphology and is expected to find various applications in mid-infrared, optoelectronic devices.