Fe/N co-doped nano-TiO2 wrapped mesoporous carbon spheres for synergetically enhanced adsorption and photocatalysis

Abstract

1 Fe/N co-doped core-shell porous carbon/TiO 2 composite was fabricated. 2 Fe, N in carbon acted as the heteroatom sources for co-doping of TiO 2 via C-TiO 2 interface. 3 Synergistic adsorption-photocatalysis was enhanced by the hierarchical structure and doping. 4 Excellent performance was confirmed for the photodegradation of paraxylene and RhB. Carbon-based adsorption and TiO 2 -based photocatalysis are both safe and low-cost ways of pollutant purification. Constructing C-TiO 2 architectures can effectively improve removal efficiency. However, most of those carbon frames only acted as supporting substrates, exhibiting rather limited synergistic action from TiO 2 and carbon. Herein, Fe/N co-doped nano-TiO 2 wrapped on mesoporous carbon spheres with a core-shell structure was designed. The Fe, N co-doped carbon sphere with a hierarchical structure improved the synergy of adsorption and transfer during the photocatalytic process. Without extra dopant, the Fe and N partly exposed on the surface realized the in-situ migrating into the TiO 2 shell to enhance the interface effect, which significantly promoted the photocatalytic efficiency of the composite. Furthermore, the photocatalytic efficiency of the composite was investigated through two typical pollutants under visible-light irradiation. The degradation efficiencies for rhodamine B and paraxylene were 96.2% in 60 min and 94.1% in 20 min, respectively, with the apparent rate constant of 0.045 min –1 and 0.049 min –1 , 8.3 and 11.4 times of that for bare TiO 2 . The composite is likely advantageous for treating diverse environmental pollutants.