N-doped carbon/TiO2 composites with enhanced photocatalytic performance for the removal of organic pollutants

Abstract

A nitrogen doped carbon (NC) material, obtained via the camphor combustion technique, was used to develop a TiO2 based visible light photocatalyst. Various physical and analytical techniques were used to characterize the structural, morphological and photocatalytic study of the obtained catalyst. The results illustrate that N-doped carbon/TiO2 composites (NCT) exhibit NC spheroids embedded on the surface of 3D flower-like hierarchical TiO2 microspheres composed of 1D nanorods. The presence of C-N, C-C, N-Ti-O and Ti-O-C was successfully confirmed by the FTIR study. The UV–vis absorption spectra revealed the energy bandgap between 2.4 and 2.8 eV, confirming the enhanced visible light absorption ability for the NCT samples with increased wt% of N-doped carbon. The NCT sample has achieved 86% photodegradation of methyl orange in an aqueous solution within 25 min under mercury light irradiation and 85% within 10 min under natural sunlight irradiation. In addition, NCT3 composite degrades 30% of BPA (20 ppm) within 210 min under mercury light irradiation. The enhanced catalytic activity of the composite material was ascribed due to the high surface area, large pore size and high pore. Also, the high absorption in the visible range and efficient charge transfer of the charge carriers were credited for the enhanced photocatalytic activity of the NCT3 sample.