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

In this letter we demonstrate the material 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 SiSn amorphous target in water at ambient conditions. Plasmas generated in liquid by laser pulses are characterized by spatial confinement with very high pressure (GPa), which allowed the growth of SiSn-ncs via kinetic pathways. We further illustrate that surface engineering by a direct-current atmospheric-pressure microplasma is capable of tailoring SiSn-ncs surface properties without the need of lengthy surfactants and 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.