Carbon-modified TiO2 nanourchin with Ag nanoparticle decoration for environmental remediation

Multifunctional critical nano-composite material assembling Carbon-modified Ag@TiO2 nanourchin was synthesized to investigate visible light photocatalytic activity. The Carbon-modified Ag@TiO2 nanourchin was prepared by a facile two-step chemical synthesis through solvothermal and chemical reduction. Carbon nanospheres as the substrate play a key role for three dimensional nanourchin structure as well as carbon doping. The morphology, crystal structure, and chemical states were characterized carefully by different analytical procedures via transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDAX), X-ray diffraction (XRD), RAMAN spectroscopy, X-ray photoelectron spectroscopy (XPS) and UV-Vis spectroscopy. It shows that the uniform loaded silver (Ag) on TiO2 surface was metallic Ag-0 state. The exist of interstitial carbon and Ag NPs on TiO2 nanostructure collectively enhance the visible light photocatalytic activity. The visible light photocatalytic degradation of methyl orange (MO) studies revealed that Ag@C0.1TiO2 exhibited enhanced photocatalytic efficiency compared with the pure TiO2 nanourchin and commercial TiO2 powder. The improved photocatalytic property can be attributed to lower recombination of the photogenerated e(-) and h(+) pairs in catalyst due to the formation of a Schottky barrier between Ag NPs and TiO2 which improved the surface charge separation greatly and presence of carbon serve as a sensitizer to absorb visible light which inject e- into conduction band (CB) of TiO2.

Automated summary

A multifunctional critical nano-composite material, Carbon-modified Ag@TiO2 nanourchin, was synthesized to investigate its visible light photocatalytic activity. The carbon-modified nanourchin was prepared by a two-step chemical synthesis method. The existence of both carbon and silver nanoparticles on the TiO2 nanostructure enhanced the visible light photocatalytic activity. The experimental results showed that the carbon-modified nanourchin exhibited higher photocatalytic efficiency compared to pure TiO2 nanourchin and commercial TiO2 powder. This improvement can be attributed to the formation of a Schottky barrier between silver nanoparticles and TiO2, which greatly improved the surface charge separation, as well as the presence of carbon serving as a sensitizer to absorb visible light and inject electrons into the conduction band of TiO2.