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.

Centrifuge enforced precipitation was used to disperse PbS quantum dots (diameter 4.7 nm) on polyethylene terephthalate. By employing double frequency Fourier transform spectroscopy, we studied the emission properties of the sample. Gaussian shaped emission spectra from cryogenic temperatures up to room temperatures were observed, demonstrating the potential of PbS quantum dots to be used as light emitters in combination with organic matrices. One interesting feature is that the linewidth of the emission spectrum does not follow the expected thermal broadening.