Sn(4+)and S(2-)co-doped N-TiO(2-x)nanoparticles for efficient and photocatalytic removal of contaminants

摘要

N-TiO(2-x)nanoparticles (NPs) were selected as a basic construction unit because there are many Ti(3+)and O vacancies on its surface. When S(2-)and Sn(4+)are co-doped into the N-TiO(2-x)lattice, the O(2-)and Ti(4+)atoms can be replaced, respectively. The formation of dopant energy levels from Sn(4+)and S(2-)in Sn4+/S2-/N-TiO(2-x)causes an obvious red shift to the visible light region. The recombination rate of the e(-)/h(+)pairs was significantly reduced due to the fast migration and separation of the electrons as a result of the energy level doping from Sn(4+)and S(2-)and the formation of electron traps with Sn4+. The N-TiO2-xNP band gap was significantly narrowed from 3.07 eV to 0.77 eV upon co-doping with Sn(4+)and S2-, resulting in the superior photocatalytic activity of the Sn4+/S2-/N-TiO(2-x)NPs. The photocatalytic reduction rate of Cr(vi) increased by 11.6 times and the photodegradation rate of doxycycline hydrochloride (DH) achieved about 5.7 times that of the original N-TiO(2-x)NPs. This study provided a simple approach to preparing metal and non-metal co-doped N-TiO(2-x)NPs, which could greatly improve the removal efficiency of contaminantsviatheir synergistic effect.