Porous graphitic carbon nitride with a high surface area was successfully synthesized without using any template or other substances like metals, just by placing melamine powder into a muffle furnace which was heated to 550 degrees C in advance. To evaluate the structure, morphology, and optical properties, the high performance g-C3N4 (HPCN) was analyzed by XRD, SEM-EDX, TEM, N-2 physisorption, FT-IR analysis, UV-Vis DRS, PL, and Zeta potential. HPCN was able to completely degrade rhodamine B under visible light with the rate constant of 0.086 min(-1), which is 3.5 times higher than the traditional g-C3N4. The possible mechanism of RhB photodegradation was discussed in detail, which illustrated the reaction is performed in acidic media much better than neutral and basic solutions, and O-center dot(2) and h(+) are the key reactive species during the reaction. Moreover, the stability of the photocatalyst was investigated and turned out its photocatalytic activity has not considerably changed after 6 cycles, so it was a highly stable photocatalyst. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.