▎ 摘　　要

The increasing occurrence of algal blooms with harmful algae-derived organic matters as microcystin-LR (ML-LR) has become an urgent public health issue. In this study, the preparation of g-C3N4 with changing the ratio of urea to melamine in the precursor was studied for MC-LR degradation under visible light. The prepared photocatalysts were characterized by scanning electron microscopy (SEM), Xray diffraction (XRD), fourier transform infrared spectrometry (FTIR) and UV-vis diffuse reflection spectroscopy (DRS) methods. The results show that the prepared photocatalysts exhibit the different structure and properties with the different mass ratio of urea to melamine. The photocatalyst CN(32) with porous structure and high photocatalytic activity has improved the degradation rate of MC-LR compared with other photocatalysts. It shows that the degradation rate of MC-LR to CN(32) is 23.68% which is 1.8 and 2.2-folds higher than that of CN(10) and CN(01), respectively. This finding can guide us to prepare photocatalysts with high activity based gC(3)N(4) for degrading microcystins