In situ synthesis of g-C3N4/TiO2 with {001} and {101} facets coexposed for water remediation

A relatively simple and bottom-up method has been developed for the preparation of g-C3N4/TiO2 nano-composites with coexposed {001} and {101} facets. Under acid-assisted hydrothermal conditions, the supramolecular preassembly of triazine precursor was resulted from the coordination of melamine with induced cyanuric acid, and synchronized with the large-scale etching of TiO2. Consequently, the g-C3N4/TiO2 nano-composites with coexposed {001} and {101} facets have been prepared via the simple heat treatment process. As the sintered precursor, the self-assembled supramolecules serve as a viable means for simultaneously controlling the compact and uniform contact interfaces between g-C3N4 and TiO2. As a result, the obtained samples exhibit excellent visible photocatalytic performance for the degradation of organic pollutants and inactivation of Escherichia coli K-12 as compared to pristine g-C3N4 and TiO2 The reactive center dot O-2(-) and photoinduced holes are found to play the major roles in the photocatalytic behavior due to the energy band structure of the materials. Our results suggest that the self-assembled supramolecules can serve as the sintered precursor to prepare a high photocatalytic performance material on the field of water treatment, and pave alternative synthetic method for composites based on conjugated polymers and metallic compound.