Synthesis and characterization of sulfur self-doped g-C3N4 with efficient visible-light photocatalytic activity

• Sulfur self-doped g-C3N4 has been synthesized by directly heating thiourea in air.
• The sample prepared at 550 °C has a highest visible light photocatalytic performance.
• The unique layered structure and S-doping can improve the photocatalytic activity.
• Our findings can offer useful insights for development of efficient photocatalysts.

In this study, we reported on our successful attempt to synthesize sulfur self-doped g-C3N4 by directly heating thiourea in air. The effects of treating temperature on the structural, optical and photocatalytic properties of the samples were investigated. The results demonstrated that S atoms have been incorporated into the g-C3N4 and may preferentially occupy N sites. The S-doped g-C3N4 sample prepared at 550 °C presented a highest photocatalytic activity in the degradation of methyl blue under visible-light irradiation. The special two-dimensional layered structure and appropriate S-doping could be responsible for the superior visible-light photocatalytic performance.