© Mohamed Nawfal Ghazzal et Erwan Paineau
| The discovery of new, cost-effective materials free of precious metals, while maintaining high catalytic performance, is of great interest for the electrochemical dissociation of water. A consortium led by researchers from the Solid State Physics Laboratory and the Institute of Physical Chemistry (CNRS/UPSaclay) has demonstrated how geoinspired clay nanotubes can constitute a sustainable and reliable electrocatalyst for the oxygen evolution reaction in electrochemical processes. |
The oxygen evolution reaction (OER) is a well-known process that requires the transfer of four electrons while competing with peroxide formation. In recent years, significant progress has been made with Ir- and Ru-based catalysts, which are considered benchmark materials for OER. However, despite their high activity and stability, the scarcity of these elements and their high cost pose significant challenges for large-scale application compared to more abundant elements on Earth. Geo-inspired nanotubes, such as germanium-based imogolite (GeAl2O3(OH)4, Ge-NTI), are novel materials whose tubular structure and composition make them promising for catalytic reactions. Furthermore, selective isomorphic substitution of the different elements in their structure is possible, offering a simple way to modulate their conductivity and catalytic properties, although preserving the original tubular structure remains a major challenge.
This is the strategy pursued by a national consortium of researchers from the universities of Paris-Saclay, Cergy, and Poitiers, in collaboration with scientists from the SOLEIL Synchrotron beamline. Through a one-step hydrothermal synthesis, iron atoms were successfully incorporated into the structure of germanium imogolite, following the general structural formula Ge(Al2-2xFe2x)O3(OH)4. For a substitution ratio x = [Fe]/([Al]+[Fe]) less than 0.1, the original properties of the nanotubes are preserved, such as their monodisperse diameter, colloidal stability, and unique self-organizing properties.
Reference
Yassine Naciri, Jian Li, Wahid Ullah, Fabien Baron, Franck Bourdelle, Stéphan Rouzière, Claire Goldmann, Erik Elkaim, Thomas Bizien, Rachid Belkhou, Delphine Vantelon, Mohamed Nawfal Ghazzal & Erwan Paineau
Iron-Doped Ge-Imogolite Nanotubes as Noble-Metal-Free Electrocatalysts for the Oxygen Evolution Reaction
Advanced Functional Materials 2025
https://advanced.onlinelibrary.wiley.com/doi/full/10.1002/adfm.202515690
Contact
Mohamed Nawfal Ghazzal, Enseignant-chercheur à l’Institut de chimie-physique (CNRS/Université Paris-Saclay) : mohamed-nawfal.ghazzal@universite-paris-saclay.fr
Erwan Paineau, Chercheur au Laboratoire de physique des solides (CNRS/Université Paris-Saclay): erwan-nicolas.paineau-lanone@cnrs.fr
Communication CNRS Chimie : cnrs-chimie.communication@cnrs.fr