Design strategies for SCR catalysts with improved N2 selectivity: the significance of nano-confining effects by titanate nanotubes

作者：Chen, Xiongbo; Wang, Penglu; Fang, Ping; Wang, Haiqiang^*; Cen, Chaoping^*; Zeng, Wenhao; Wu, Zhongbiao

来源：Environmental Science: Nano , 2017, 4(2): 437-447.

DOI：10.1039/c6en00627b

• LOW-TEMPERATURE SCR
• IMPROVED RESISTANCE
• PROMISING CATALYST
• OXIDE CATALYSTS
• TIO2 NANOTUBES
• REDUCTION SCR
• N2O FORMATION
• NO
• NH3
• COPPER

Copper has been investigated as a promising alternative for SCR reactions. However, most Cu-based catalysts supported on zeolites, alumina or titania produced a certain amount of undesired N2O by-product. Herein, we report a strategy to tune the redox properties of copper oxides via confinement within titanate nanotubes (Cu/TNTs) and investigate their SCR activity as well as the N-2 selectivity. The Cu/TNT catalyst showed an excellent NO reduction performance (above 90%) in the temperature window of 300-450 degrees C and the N2 selectivity could exceed 98% among the whole reaction temperature range of 150-470 degrees C, with a negligibly low concentration of N2O being detected. After systematic characterizations, the tuning of the chemical state of copper and oxygen, the remarkable adsorption capability, the accelerated oxidation of Cu+ to Cu2+, the lower level of NH3 oxidation and ultimately the tuning of redox properties were discovered. This work could provide a new approach to design SCR catalysts with superior catalytic reduction performance as well as excellent N-2 selectivity.

• 出版日期2017-2-1
• 单位浙江大学; 环境保护部华南环境科学研究所