Efficient yield of reactive-oxygen species (ROS) is greatly important for environmental purification and engineering. In this study, the perfected pi-conjugated g-C3N4 (P-Na-g-C3N4) photocatalysts were constructed by coordination between 3p orbits of Na and N 2p lone electron at vacancy structure of tri-s-triazine polymer for ROS evolution and elimination of HCHO and NO. The perfected pi-conjugated structure enhances the visible-light capturing capability, enriches active sites for O-2 activation, and promotes the directional charge transfer from N 2p of C-3-N to Na and C. Therefore, the superior activities including the evolution of O-2(-) (35 mu mol.L(-1)h(-1)), and H2O2 (517 mu mol.L(-1)h(-1)) have been achieved over P-Na-g-C3N4 photocatalyst. As a result, P-Na-g-C3N4 photocatalysts demonstrate high performances removal efficiency of NO (53% for 6 min), and HCHO (almost 100% for 55 min) in the elimination process. The results may provide the promising strategy to construct efficient photocatalytic system to yield ROS for environmental purification. (C) 2018 Elsevier Inc. All rights reserved.