Pivotal role of fluorine in enhanced photocatalytic activity of anatase TiO₂ nanosheets with dominant (0 0 1) facets for the photocatalytic degradation of acetone in air

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• 作者：Quanjun Xiang ; Kangle Lv ; Jiaguo Yu
• 关键词：TiO₂ nanosheets ; { ; 0 0 1} facets ; Hydrothermal route ; Surface fluorination ; Photocatalytic activity
• 刊名：Applied Catalysis B: Environmental
• 出版年：2010
• 出版时间：7 June 2010
• 年：2010
• 卷：96
• 期：3-4
• 页码：557-564
• 全文大小：1141 K

文摘

Surface-fluorinated anatase TiO₂ nanosheets with dominant {0 0 1} facets were fabricated by a simple hydrothermal route in a Ti(OC₄H₉)₄-HF-H₂O mixed solution. The atomic ratios of fluorine to titanium (R_F) exhibit an obvious influence on the structures and photocatalytic activity of TiO₂ samples. In the presence of HF, TiO₂ nanosheets can be easily obtained. With increasing R_F, the relative anatase crystallinity, average crystallite size, pore size and percentage of exposed {0 0 1} facets increase, contrarily, BET specific surface areas decrease. All fluorinated TiO₂ nanosheets exhibit much higher photocatalytic activity than Degussa P-25 TiO₂ (P25) and pure TiO₂ nanoparticles prepared in pure water due to the synergistic effect of surface fluorination and exposed {0 0 1} facets on the photoactivity of TiO₂. Especially, at R_F = 1, the fluorinated TiO₂ nanosheet exhibits the highest photocatalytic activity, and its photoactivity exceeds that of P25 by a factor of more than nine times.