Halogen atom effect on organic luminescence materials incorporating arylsulfonylated phenothiazine as the central unit was investigated in both solid state and organic solution. New organic solids with very weak C-halogen center dot center dot center dot pi interactions are constructed, in which the packing style totally avoids the face-to-face stacking. Consequently, a high solid luminescent efficiency (81.37%) is obtained from a fluorine-substituted organic molecule crystal. The halogen atom effect on photocatalytic reaction was evaluated using arylsulfonylated phenothiazines, which catalyzed dehydrogenative coupling of amines to imines by simple blue light irradiation of the acetonitrile solution under aerobic atmosphere. The chlorine- substituted photocatalyst exhibited a higher reactivity than other ones, providing a preliminary insight for rational photocatalysts modification. (C) 2020 Elsevier Inc. All rights reserved.