Abstract: A novel graphene-based nanocomposite composed of tris(4,4′-dicarboxy-2,2′-bipyridine) ruthenium chloride (Ru(dcbpy)3) sensitized TiO2 and reduced graphene oxide (RGO) was prepared by a colloidal blending method and characterized by X-ray diffraction, high-resolution transmission electron microscopy, Raman spectroscopy and UV–vis diffuse reflectance spectroscopy. The nanocomposite demonstrated nice photocatalytic activity and stability for water reduction to produce hydrogen. The amount of H2 evolved from the optimized Ru(dcbpy)3/TiO2/RGO/Pt catalyst is 959μmolg−1 at pH 3 under 5h visible-light irradiation. [Copyright &y& Elsevier]