Visible light activated carbon and nitrogen co-doped mesoporous TiO2 as efficient photocatalyst for degradation of ibuprofen

Abstract Carbon and nitrogen co-doped mesoporous TiO 2 photocatalysts with tunable brookite/anatase ratios controlled by glycine assistant were synthesized through one-pot hydrothermal process. Structural investigations indicated a formation of pure brookite TiO 2 nano-spindles in the absence of glycine, while when glycine was added, mesoporous heterojunction TiO 2 nanoparticles consisted of small quasi-spherical anatase and brookite nanorods were obtained. The band gap of the optimum C and N doped TiO 2 was 2.85 eV, indicated the formation of a visible light-activated photocatalyst. XPS and FT-IR results identified C C, C H and N H bonds, providing clear evidence for doping of nitrogen and carbon into mesoporous TiO 2 network. The photocatalytic activity of all prepared catalysts was investigated via photodegradation of ibuprofen (IBF) solutions under visible light and UV illumination. The samples obtained at 74.4% anatase/25.6% brookite heterojunction TiO 2 using 1 M glycine exhibited the highest activity, due to its superior properties under visible light illumination with 99% photodegradation efficiency. Moreover, the PL results showed that the e − /h + recombination rate of the optimal sample was significantly reduced compared to other prepared samples using more or less 1 M glycine content. The improved photocatalytic activity of the optimal sample was attributed to large surface area, heterostructure formation, and high absorption in the visible range and efficient separation of the charge carriers. This study elucidates a facile method for TiO 2 synthesis with different mixtures of TiO 2 polymorphs with desirable properties for various potential applications.