Exploring visible light responsive media remains a challenge for solar energy photocatalysis applications. We report the Ni3S2-reduced graphene oxide (NG) hybrid composites with sheet-on-sheet structures synthesized by a facile microwave-assisted method. Their morphology, structure and photocatalytic activity in the reduction of Cr(VI) were characterized by scanning electron microscopy, X-ray diffraction, UV Vis absorption spectroscopy, and electrochemical impedance spectra, respectively. The results show that NG hybrid composites show excellent visible light photocatalytic activity in the reduction of Cr(VI) compared to pure Ni3S2. The Cr(VI) reduction rate of higher than 90% has been achieved with 1 wt.% reduced graphene oxide under visible light irradiation at 180 min. Improvement is attributed to its efficient charge separation and more active sites due to the integrative effect and good interfacial contact between Ni3S2 and reduced graphene oxide. (C) 2017 Elsevier Inc. All rights reserved.