An in situ study with dispersive EXAFS (Extended X-Ray Absorption Spectroscopy) at the Ir-LIII edge is performed to characterize Electrodeposited Iridium Oxide Films (EIROF) under chronoamperometric conditions. The technique monitors the local chemical environment and electronic structure of iridium during the oxidation of Ir(III) to Ir(IV) with a time resolution of milliseconds. The study is performed in both acidic and basic media. The Fourier transforms of the time-resolved EXAFS signals clearly show that the short-range structure of Ir is similar to that of rutile-type IrOand is maintained during the reaction, thus accounting for the flexibility of the structure of the electrode material in accommodating different oxidation states. From a more general point of view, the work demonstrates the capabilities of in situ experiments based on state-of-the-art dispersive EXAFS in clarifying the mechanistic aspects of electrochemical processes.

In situ dispersive EXAFS in electrocatalysis : the investigation of the local structure of IROx in chronoamperometric conditions as a case study / E. Achilli, A. Minguzzi, O. Lugaresi, C. Locatelli, S. Rondinini, G. Spinolo, P. Ghigna. - In: JOURNAL OF SPECTROSCOPY. - ISSN 2314-4920. - 2014(2014), pp. 480102.1-480102.7.

In situ dispersive EXAFS in electrocatalysis : the investigation of the local structure of IROx in chronoamperometric conditions as a case study

A. Minguzzi
Secondo
;
O. Lugaresi;C. Locatelli;S. Rondinini;
2014

Abstract

An in situ study with dispersive EXAFS (Extended X-Ray Absorption Spectroscopy) at the Ir-LIII edge is performed to characterize Electrodeposited Iridium Oxide Films (EIROF) under chronoamperometric conditions. The technique monitors the local chemical environment and electronic structure of iridium during the oxidation of Ir(III) to Ir(IV) with a time resolution of milliseconds. The study is performed in both acidic and basic media. The Fourier transforms of the time-resolved EXAFS signals clearly show that the short-range structure of Ir is similar to that of rutile-type IrOand is maintained during the reaction, thus accounting for the flexibility of the structure of the electrode material in accommodating different oxidation states. From a more general point of view, the work demonstrates the capabilities of in situ experiments based on state-of-the-art dispersive EXAFS in clarifying the mechanistic aspects of electrochemical processes.
Settore CHIM/02 - Chimica Fisica
2014
Article (author)
File in questo prodotto:
File Dimensione Formato  
33_JSpectr_2015.pdf

accesso aperto

Tipologia: Publisher's version/PDF
Dimensione 1.99 MB
Formato Adobe PDF
1.99 MB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/338290
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 11
  • ???jsp.display-item.citation.isi??? 9
social impact