Reduction of NO by CO catalyzed by Fe-oxide/Al2O3: Strong catalyst-support interaction for enhanced catalytic activity

• Published in: Applied surface science 2020-04, Vol.509, p.145300, Article 145300
• Main Authors: Cha, Byeong Jun, Kim, Il Hee, Park, Chan Heum, Choi, Chang Min, Sung, Ji Yeong, Choi, Myoung Choul, Kim, Young Dok
• Format: Article
• Language: English
• Subjects: Catalyst-support interaction; NO reduction by CO; Secondary ion mass spectrometry
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2020.145300

[Display omitted] •Fe-oxide nanoparticles were deposited on mesoporous Al2O3 using temperature regulated chemical vapor deposition.•Catalytic activity for NO reduction by CO increased with the post-annealing temperature or time of Fe-oxide/Al2O3.•Enhanced interaction between Al2O3 and Fe-oxide was suggested to be responsible for the increased catalytic activity. Fe-oxide/Al2O3 catalysts were fabricated by depositing Fe-oxide nanoparticles with a lateral size less than ~2 nm in a highly dispersed manner within mesoporous Al2O3 using temperature-regulated chemical vapor deposition (TRCVD). The Fe-oxide/Al2O3 catalysts were post-annealed at either 450 °C (for 2 h) or 750 °C (for 2 or 8 h) and were used to catalyze NO reduction by CO. Catalytic activity was significantly enhanced with increased annealing temperature and time. Secondary ion mass spectrometry using Bi3+ as the primary ion shows an increase in the FeAlO+ signal from the interfaces between Fe-oxide and Al2O3 with increasing annealing temperature and time, suggesting that the enhanced interaction between Al2O3 and Fe-oxide is responsible for the increased catalytic activity. It is shown that TRCVD with a proper post-annealing step is a competitive tool for preparation of heterogeneous catalysts with highly dispersed catalyst nanostructures within mesoporous substrates that contain rich oxide/oxide interfaces and allow enhanced catalytic activity.