Colloidal nanoparticles (NPs) can be deposited uniformly on flat or rough and uneven substrate surfaces employing a standard centrifuge and common solvents. This method is suitable for depositing different types of nanoparticles on a variety of substrates including glass, silicon wafer, aluminum foil, copper sheet, polymer film, plastic, and paper, etc. The thickness of the films can be controlled by the amount of the colloidal nanoparticle solution used in the preparation. The method offers a fast and simple procedure compared to other currently known nanoparticle deposition techniques for studying the optical properties of nanoparticle films.

Insulating oxide films can be produced by hydrolysis of metal alkoxide precursors in the presence of an acid catalyst in supercritical fluid carbon dioxide (sc-CO₂).

PbS QDs of different sizes are deposited with supercritical fluid CO ₂ to form laterally uniform PbS QD films as compared to other deposition methods. Luminescence studies show FRET process and different transient life times.