title: Observing Pt nanoparticle formation at the atomic level during polyol synthesis.
abstract: This study investigated the synthesis of platinum nanoparticles (Pt NPs) in ethylene glycol using low cost and low toxicity chemicals as reducing (ascorbic acid) and stabilizing agents (polyvinylpyrrolidone and sodium citrate). By monitoring the changes in the local chemical environment of the Pt atoms in real time by in situ dispersive X-ray absorption spectroscopy, it is observed that the NP formation kinetics involved three different stages within 3 h 30 min of the reaction: a reduction-nucleation burst, followed by diffusion-limited Ostwald ripening growth and subsequent stabilization of the NPs. The resulting Pt NPs were analyzed by transmission electron microscopy and X-ray diffraction, revealing a monodisperse average size distribution of 2.7 ± 0.5 nm, characterized by highly crystalline and stable Pt clusters, showing no significant aging for at least nine months.
authors.affiliation: Laboratório de Espectroscopia de Elétrons (LEe-), Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500, Bairro Agronomia, CP 15051, CEP 91501-970, Porto Alegre, RS, Brazil. jonder@if.ufrgs.br.
authors.forename: Jocenir
authors.initials: J
authors.lastname: Boita
authors.forename: Lucas
authors.initials: L
authors.lastname: Nicolao
authors.forename: Maria C M
authors.initials: MC
authors.lastname: Alves
authors.forename: Jonder
authors.initials: J
authors.lastname: Morais