Abstract g-C 3 N 4 has received extensive attention because of its good chemical stability and environmental friendliness. Since g-C 3 N 4 prepared from various precursors had different photocatalytic activities, g-C 3 N 4 materials marked as U-gCN, D-gCN and M-gCN were synthesized from various precursors of urea, dicyandiamide and melamine, respectively. The D-gCN and M-gCN with smaller surface area were heated again to obtain exfoliated g-C 3 N 4 with 2D nanosheet morphology and larger specific surface area named D-gCN-L and M-gCN-L, respectively. The synthesized bulk g-C 3 N 4 and g-C 3 N 4 2D nanosheets were characterized by XRD, SEM, BET, PL, UV-Vis diffuse reflectance spectroscopy, XPS, zeta potential and TG. The photocatalytic degradation of methylene blue (MB) was carried out on U-gCN, D-gCN, M-gCN, D-gCN-L and M-gCN-L, and D-gCN-L shows the highest photocatalytic degradation performance because of its larger specific surface area, lower electron-hole recombination and wide light absorption range.

中文翻译：

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以双氰胺为前驱体通过热剥离增强 g-C3N4 2D 纳米片的光催化活性

摘要 gC 3 N 4 因其良好的化学稳定性和环境友好性而受到广泛关注。由于由各种前体制备的gC 3 N 4 具有不同的光催化活性，因此分别以尿素、双氰胺和三聚氰胺的各种前体合成了标记为U-gCN、D-gCN和M-gCN的gC 3 N 4 材料。再次加热具有较小表面积的 D-gCN 和 M-gCN 以获得具有二维纳米片形态和较大比表面积的剥离 gC 3 N 4 ，分别命名为 D-gCN-L 和 M-gCN-L。通过XRD、SEM、BET、PL、UV-Vis漫反射光谱、XPS、zeta电位和TG表征合成的块状gC 3 N 4 和gC 3 N 4 2D纳米片。在U-gCN、D-gCN、M-gCN、D-gCN-L和M-gCN-L上进行了亚甲基蓝（MB）的光催化降解，