Surface and luminescent properties of copper activated zinc sulfide phosphors were studied. It was shown that measurements of the distribution of active surface centers (DAC) provides a tool of precise study of the surface chemical composition as well as probe for surface structural defects. Correlation between phosphor synthesis and annealing conditions, donor-acceptor properties of its surface and its electroluminescent characteristics was shown. (c) 2004 Elsevier B.V. All rights reserved.