Higher visible photocatalytic activities of nitrogen doped In₂TiO₅ sensitized by carbon nitride

N-doped In₂TiO₅ modified by carbon nitride (CN) composite (NICN) has been prepared by the pyrogenation of the mixture of urea and In₂TiO₅ through a polymerizable complex (PC) method. The powder samples were characterized by XRD, FESEM, TEM, UV-vis, and XPS. It is shown by XRD that the precursor sintered at 1000°C is pure and nitrogen dopant does not change the crystal structure of In₂TiO₅. FESEM and TEM reveal a hole-like morphology of the prepared NICN. With the increase of nitrogen content, the light absorption onset of In₂TiO₅ shifts from 410nm to 450nm, revealing significant narrowing of the band gap. XPS results suggest that only 2.2% of the nitrogen atoms were doped into In₂TiO₅ through the urea pyrogenation method. Furthermore, the decomposition of Rhodamine B (Rh-B) under visible light reveals that Rh-B can be degraded completely within 20min and recycling experiments indicate NICN has stable structure and durable photocatalytic activity, suggesting a promising utilization of such photocatalyst under visible light. Finally, an innovative mechanism of N-doped In₂TiO₅ sensitized by carbon nitride polymer is proposed.