A highly efficient, eco-friendly, and visible-light-driven photocatalyst, namely nitrogen doped titanium dioxide (N-TiO2)/collagen-polyvinyl pyrrolidone (ASC-PVP) hybrid nanocomposite is prepared via facile sol-gel method. The ASC-PVP steadily covers the N-TiO2. The XPS data confirmed the oxygen vacancies and nitrogen interstitial-type doping in N-TiO2 prepared by the sol-gel route. Furthermore, the O 1s and N 1S XPS data prove that both nitrogen and oxygen atoms of ASC-PVP are participated in hydrogen bonds with N-Ti-O and/or Ti-O-N bonds in N-TiO2 nanoparticles. Moreover, the N-TiO2/ASC-PVP is shown an obvious red shift of absorption band edge and reduced recombination rate of electron-hole in comparison with N-TiO2 nanoparticles. N-TiO2/ASC-PVP was used to study photocatalytic degradation of a typical polycyclic aromatic hydrocarbon (PAHs), namely naphthalene in water under visible light irradiation. N-TiO2/ASC-PVP possessed high photocatalytic activity for the naphthalene degradation (86%) within 100 min under visible light. The inhibitory effect on the naphthalene photodegradation indicated that and h+•are the major reactive species. Also, the N-TiO2/ASC-PVP exhibited very good visible light photocatalytic efficiency for the removal of naphthalene at very low concentrations from seawater.
