Cerium-doped Lu4Si2O7N2 green phosphors were synthesized by a high-temperature solid-state reaction method under nitrogen atmosphere. Compared with Ce-doped Y4Si2O7N2 phosphors, Ce-doped Lu4Si2O7N2 phosphors showed longer wavelengths of both excitation and emission, lower Stokes shift and much stronger emission intensity. Based on the first-principles calculations of the two phosphors strong emission intensity originates from the large density of states. At last, the effects of concentration on photoluminescence were also examined. (C) 2009 Elsevier B.V. All rights reserved.