Determination of nanoobject sizes in porous systems, nanomaterials, and some defective materials using the positron annihilation spectroscopy method (survey)

It is shown that the positron annihilation spectroscopy (PAS) method is one of the most effective ways of determining the sizes of nanoobjects (vacancies, vacancy clusters, free pore spaces, cavities, and voids) and their concentrations in the place of annihilation of positrons in porous systems and in a wide range of technically important materials and nanomaterials. The possibilities of the method are demonstrated by example of porous silicon and silicon irradiated with protons.