LAUSR

Abstract g-C 3 N 4 with uniformly porous structure is very attractive owing to its special surface and interface properties in photocatalytic field. Herein, uniformly porous sulfur doped C 3 N 4 /carbon dot (S-C 3 N 4 /C-dot) composite with narrow pore size distribution was successfully synthesized via a facile one-step calcination of S-C 3 N 4 precursor with the prefabricated C-dot, rather than employing any other template materials. Experiments found, it was the C-dot that served as the pore-forming agent via its own oxidation into gaseous products, and ratio of C-dot in the raw material played a key role in controlling the crystal structure, morphology and photocatalytic property of the final products. With the optimum ratio, the obtained S-C 3 N 4 /C-dot composite exhibited a superior activity in antibiotics degradation compared with pure S-C 3 N 4 , which was attributed to the unique pore structure, large specific surface area, strong visible light absorption and less recombination of electron-hole pairs. In addition, trapping experiments and intermediate product analyses were also carried out to understand the antibiotics removal mechanism and pathways. This study is very helpful to deeply understand the function of C-dot decoration, and declare the great potential of g-C 3 N 4 in practical water purification.