Preparation of polymer-protected semiconductor nanoparticles through the rapid expansion of supercritical fluid solution

Poly(N-vinyl-2-pyrrolidone)-stabilized semiconductor cadmium sulfide nanoparticles with an average particle size of ∼33 Å were prepared by using a new method based on the rapid expansion of supercritical solution. The nanoparticles were characterized by use of UV/Vis diffuse reflectance spectroscopy, powder X-ray diffraction, luminescence, and transmission electron microscopy methods.