Near infrared to visible up-conversion luminescence in Er3+ single doped BaCl2, BaF2 and NaYF4 phosphors were compared. Intense blue emission at 410 nm due to H-2(9/2) -> I-4(15/2) transition and greenish-blue emission at 496 nm due to F-4(7/2) -> I-4(15/2) transition were only observed in BaCl2:Er3+ when excited by 808 nm and 976 nm laser diodes, respectively. The phenomena can be ascribed to the direct two-step excitation processes which occur in the chlorides where multiphonon relaxation is rapidly suppressed. In addition, the intensity of upconversion emission in BaCl2:Er3+ is greatly enhanced upon broadband near-infrared excitation. (C) 2015 Elsevier B.V. All rights reserved.