%0 Journal Article
%A Minguzzi, Alessandro
%A Locatelli, Cristina
%A Lugaresi, Ottavio
%A Achilli, Elisabetta
%A Cappelletti, Giuseppe
%A Scavini, Marco
%A Coduri, Mauro
%A Masala, Paolo
%A Sacchi, Benedetta
%A Vertova, Alberto
%A Ghigna, Paolo
%A Rondinini, Sandra
%D 2015
%T Easy Accommodation of Different Oxidation States in
Iridium Oxide Nanoparticles with Different Hydration Degree as Water
Oxidation Electrocatalysts
%U https://acs.figshare.com/articles/journal_contribution/Easy_Accommodation_of_Different_Oxidation_States_in_Iridium_Oxide_Nanoparticles_with_Different_Hydration_Degree_as_Water_Oxidation_Electrocatalysts/2134570
%R 10.1021/acscatal.5b01281.s001
%2 https://acs.figshare.com/ndownloader/files/3768406
%K Different Hydration Degree
%K XRPD
%K Iridium Oxide Nanoparticles
%K IrOx
%K IrO 2 shell
%K HR
%K pair distribution function
%K Water Oxidation ElectrocatalystsIn
%K material
%K synchrotron radiation techniques
%K TEM
%K operando XAS experiments
%K Different Oxidation States
%K PDF
%K transmission electron microscopy
%K Ir core
%X In
this paper, we present a comprehensive study on low hydration Ir/IrO2 electrodes, made of an Ir core and an IrO2 shell,
that are designed and synthesized with an innovative, green approach,
in order to have a higher surface/bulk ratio of Ir–O active
centers. Three materials with different hydration degrees have been
deeply investigated in terms of structure and microstructure by means
of transmission electron microscopy (TEM) and synchrotron radiation
techniques such as high-resolution (HR) and pair distribution function
(PDF) quality X-ray powder diffraction (XRPD), X-ray absorption spectroscopy
(XAS), and for what concerns their electrochemical properties by means
of cyclic voltammetry and steady-state I/E curves. The activity of these materials is compared and
discussed in the light of our most recent results on hydrous IrOx. The main conclusion of this study is that the Ir core is noninteracting
with the IrOx shell, the latter being
able to easily accommodate Ir in different oxidation states, as previously
suggested for the hydrated form, thus explaining the activity as electrocatalysts.
In addition, in operando XAS experiments assessed that the catalytic
cycle involves Ir(III) and (V), as previously established for the
highly hydrated IrOx material.
%I ACS Publications