Photoinduced electron transfer and separation from its home atom to form spatial isolated electron/hole pairs is the most crucial factor in artificial photocatalysis field. The scalable production of nanoscale g-C3N4 with remarkable electron separation efficiency in one-step, green, economic and "bottom-up" approach is of great challenge. Herein, one-dimensional porous architectural g-C3N4 nanorods have been facilely prepared by direct calcination of hydrous melamine nanofibers precipitated from aqueous solution of melamine. Porous morphologies with increased interfacial area enhance light capture capacity and accelerate catalysis reaction. It is noted that oxygen atoms were simultaneously doped into g-C3N4 matrix, which broke the symmetry of pristine g-C3N4, resulting in more effective separation of electron/hole pairs. Thus, the oxygen-doped g-C3N4 nanorods loaded with Pt presented excellent visible-light photocatalytic hydrogen evolution in the triethanolamine solution (732 mu mol g(-1) h(-1)) and in overall water splitting (29.6 mu mol g(-1) h(-1)), and 2,4-dinitrophenol degradation for O-doped g-C3N4 nanorod (removal efficiency of 100% within 75 min). Subsequently, the visible-light photocatalytic H-2 evolution (96 mu mol g(-1) h(-1)) with simultaneous 2,4-dinitrophenol degradation were achieved for Pt@g-C3N4 nanorod. The proposed synthesis strategy overcomes long-standing, stubborn and serious stacking/agglomeration for g-C3N4 synthesis, and paves the pathway for industrial scale-up production of high-performance g-C3N4 and application in practical energy and environment area.