Immobilization of Polymeric g-C3N4 on Structured Ceramic Foam for Efficient Visible Light Photocatalytic Air Purification with Real Indoor Illumination

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• 作者：Fan Dong ; Zhenyu Wang ; Yuhan Li ; Wing-Kei Ho ; S. C. Lee
• 刊名：Environmental Science & Technology
• 出版年：2014
• 出版时间：September 2, 2014
• 年：2014
• 卷：48
• 期：17
• 页码：10345-10353
• 全文大小：577K
• ISSN：1520-5851

文摘

The immobilization of a photocatalyst on a proper support is pivotal for practical environmental applications. In this work, graphitic carbon nitride (g-C₃N₄) as a rising visible light photocatalyst was first immobilized on structured Al₂O₃ ceramic foam by a novel in situ approach. Immobilized g-C₃N₄ was applied for photocatalytic removal of 600 ppb level NO in air under real indoor illumination of an energy-saving lamp. The photocatalytic activity of immobilized g-C₃N₄ was gradually improved as the pyrolysis temperature was increased from 450 to 600 掳C. The optimized conditions for g-C₃N₄ immobilization on Al₂O₃ supports can be achieved at 600 掳C for 2 h. The NO removal ratio could reach up to 77.1%, exceeding that of other types of well-known immobilized photocatalysts. Immobilized g-C₃N₄ was stable in activity and can be used repeatedly without deactivation. The immobilization of g-C₃N₄ on Al₂O₃ ceramic foam was found to be firm enough to overwhelm the continuous air flowing, which can be ascribed to the special chemical interaction between g-C₃N₄ and Al₂O₃. On the basis of the 5,5鈥?dimethyl-1-pirroline-N-oxide electron spin resonance (DMPO ESR) spin trapping and reaction intermediate monitoring, the active species produced from g-C₃N₄ under illumination were confirmed and the reaction mechanism of photocatalytic NO oxidation by g-C₃N₄ was revealed. The present work could provide new perspectives for promoting large-scale environmental applications of supported photocatalysts.