Semiconducting quantum confined silicon–tin alloyed nanocrystals prepared by ns pulsed laser ablation in water

Abstract

Here we demonstrate the material’s synthetic feasibility for semiconducting alloyed silicon–tin nanocrystals (SiSn-NCs) with quantum confinement effects. An environmentally friendly synthesis is achieved by ns laser ablation of amorphous SiSn in water at ambient conditions. Plasmas generated in the liquid by laser pulses are characterized by spatial confinement with very high pressure (GPa), which allowed the growth of the SiSn-NCs via kinetic pathways. We further illustrate that surface engineering by a direct-current atmospheric pressure microplasma is capable of tailoring the SiSn-NCs surface properties without the need for lengthy surfactants, resulting in room temperature photoluminescence (PL); the PL peak wavelength is red-shifted by more than 250 nm with respect to the PL peak wavelengths observed for comparable elemental silicon nanocrystals.