Identification and localization of Pt species in Pt-NaA zeolite catalysts prepared by direct synthesis

YOHANA MARTÍNEZ GALEANO; MIZRAHI MARTÍN; RAMALLO LÓPEZ JOSÉ JOSÉ M; M. SERGIO MORENO; CORNAGLIA, LAURA; TARDITI, ANA M.

CATALYSIS COMMUNICATIONS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2022 vol. 172

1566-7367

Several characterization techniques were employed to elucidate the Pt species present in the structure of Pt-NaA catalysts. Three types of Pt particles were identified: nanoparticles located at he surface of the crystals (with a higher size and flattened form), 1–2 nm particles inside the structure, and sub-nanometric particles, lower than 1 nm, confined in the pores. The low Pt Pt coordination number (EXAFS) is compatible with both flattened di-hedral-like morphology, as well as he presence of sub-nanometric particles. The Pt0.6_NaA catalyst exhibited higher activity (in the GS) than the other catalysts, which could be related to the presence of small particles.