Recently, the preparation of visible-light-sensitive catalysts for the decomposition of organics has been of great interest. Herein, we report a single-step facile co-polymerization via the calcination process to produce a phenyl-modified-g-C3N4 semiconducting material. The product was characterized using standard analytical techniques. The UV/vis-DRS study indicates a shift of 23 nm toward higher wavelengths, whereas transmission electron microscopy analysis indicates the presence of phenyl group incorporation. The H-1 NMR of Ph-g-C3N4 showed a shift of aromatic proton toward down-field as compared with benzamide protons. The prepared products showed efficient performance for the removal of a dye and a drug derivative in water with light and air. The marked activity might be due to efficient light absorption and photoseparated (e(-)-h(+)) pair. The work embodied represents the construction of catalysts for the removal of organics in water with light.