1D loop chain copper(I) cluster, [Cu2I2L2](n), can be obtained based upon 9-(3-phenylselanyl-2-phenylselanylmethylpropyl)anthracene (L) and CuI. A facile in situ surface assembly strategy was designed to construct polymeric [Cu2I2L2](n), on the surface of TiO2 nanoparticles. The visible-light photocatalytic property of core-shell TiO2-[Cu2I2L2](n). was confirmed by effective reduction of aqueous chromium(VI), showing a clear correlation to optical absorption (Eg = 2.8 eV). The key points of this strategy include high reactivity between copper(I) and soft selenium atom, efficient charge-transfer through polymeric cluster shell, and visible-light photoactivity of copper(I) halogen clusters. (C) 2016 Elsevier B.V. All rights reserved.