Mesoporous Biphasic C and N Codoped Anatase Nanocrystal-Carbon Composites and their Derived Doped Anatase Nanoparticles in Phenol Elimination under Visible Light

Mesoporous C and N codoped anatase nanocrystal-carbon composites have been synthesized by chelation-assisted coassembly of urea, TiCl4, resols, and triblock copolymer. The composite catalysts have biphasic constituents in the pore walls of amorphous carbon and C,N-codoped anatase nanoparticles (approximate to 4.0nm) that are glued together; the composite catalysts also have open mesopores with high surface areas (approximate to 340m(2)g(-1)), large pore volumes (approximate to 0.20cm(3)g(-1)), and uniform pore sizes (approximate to 5.0nm). Upon calcination in air at 350 degrees C, the main-group-elements-codoped anatase nanoparticles with a size of 4.3nm can be obtained. The C,N-codoped anatase nanoparticles feature a clear redshift absorption towards the visible-light region and exhibit remarkable degradation efficiency for phenol. A repeated accumulation-photodegradation process is adopted to remove high concentrations of phenol (100mgL(-1)) from water, thereby avoiding the use of organic solvent and the posttreatment of the catalyst. After six cycles, phenol is almost completely degraded. The features of the two constituents of the composite are discussed. The mesoporous carbon support shows a high adsorption capacity for phenol, which accumulates inside its pores, and the main-group-elements-doped anatase nanoparticles can be well accessible to phenol, which it mineralizes under artificial visible light. Simultaneously, the glue role of the amorphous carbon can overcome the disadvantages of possible particle aggregation during processes and allow the catalyst to be reused.