Graphitic carbon nitride(g-C3N4)has been receiving great attention in the past years due to its promising application in photocatalysis[1].As specific morphologies often imply high photoactivity,it is of significance to develop new strategies controlling the morphologies of g-C3N4.Metal-organic supramolecular frameworks,self-assembled from metallic nodes and organic ligands through metal coordination,hydrogen bonding and π-π interactions,have been emerging as a new type of precursors for porous carbons and metal oxide/carbon composites[2].Due to the highly ordered crystalline structures,metal-organic supramolecular frameworks would be good candidates for use as both sacrificial templates and precursors to give porous g-C3N4 under proper thermal condensation conditions.Here,a facile and direct synthesis of porous nanorod-type graphitic carbon nitride/CuO composite(CuO-g-C3N4)was reported by using Cu-melamine supramolecular framework as precursor[3].The morphology of the nanocomposite was analyzed by SEM and TEM.CuO-g-C3N4 displayed porous nanorod morphology.The diameters of nanorods are smaller than 300 nm with pores about 20~50 nm along the rods.The length of nanorod could reach to 2 μm as confirmed by TEM.CuO nanoparticles around 50 nm spread on the surface of nanorods,forming hetero-structures.The CuO-g-C3N4 nanocomposite demonstrated improved visible-light-driven photocatalytic activities.After 20 min visible light irradiation,almost 94%RhB dye was degraded by CuO-g-C3N4,while only 12%and 5%RhB was degraded by g-C3N4 and CuO under the same conditions.The Z-scheme mechanism was established for the photodegradation process.Also,nanorod-type g-C3N4/Fe2O3,g-C3N4/Ag composites with significantly improved photocatalytic activities were also fabricated by applying the same strategy.The results indicate that metal-melamine supramolecular frameworks can be promising precursors for the preparation of efficient g-C3N4 nanocomposite photocatalysts.