Acidities of CeO2 and Ce0.5Zr0.5O2 solid solutions studied by NH3-TPD

✍ Scribed by Miao, Jian-Ying; Yang, Le-Fu; Cai, Jun-Xiu

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 128 KB
• Volume: 28
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(199908)28:1<123::aid-sia632>3.0.co;2-6

✦ Synopsis

Ammonia temperature-programmed desorption (NH 3 -TPD) was used to study the acidities of CeO 2 and Ce 0.5 Zr 0.5 O 2 solid solutions. The NH 3 -TPD peaks of both CeO 2 and Ce 0.5 Zr 0.5 O 2 exist at 100-850 °C. The ratio of the lower and middle temperature peak areas to the higher temperature peak is decreased for Ce 0.5 Zr 0.5 O 2 relative to CeO 2 under all pretreatment conditions, which suggests that Ce 0.5 Zr 0.5 O 2 has more acid sites of higher energy than CeO 2 . This may be one of the reasons why Ce 0.5 Zr 0.5 O 2 is a more highly efficient catalyst for methane combustion than CeO 2 .