Low-Temperature Pd/Zeolite Passive NOx Adsorbers: Structure, Performance, and Adsorption Chemistry

• Published in: Journal of physical chemistry. C Vol. 121; no. 29 p.15793-15803; pp. 15793 - 15803
• Main Authors: Zheng, Yang, Kovarik, Libor, Engelhard, Mark H, Wang, Yilin, Wang, Yong, Gao, Feng, Szanyi, János
• Format: Journal Article
• Language: English
• Published: 27.07.2017
• Subjects: adsorption; desorption; Fourier transform infrared spectroscopy; image analysis; ion exchange; ligands; nitric oxide; nitrogen dioxide; oxidation; oxygen; sodium; temperature; titration; transmission electron microscopy; trapping; X-ray photoelectron spectroscopy; zeolites

Pd/zeolite passive NOₓ adsorber (PNA) materials were prepared with solution ion-exchange between NH₄/zeolites (Beta, ZSM-5, and SSZ-13) and PdCl₂ solutions. The nature of Pd (dispersion, distribution, and oxidation states) in these materials was characterized with Na⁺ ion exchange, TEM imaging, CO t...