Projet ANR OERKOP

Oxygen evolution reaction: the key to optimize photocatalytic water oxidation (01/04/2023 - 31/03/2027)

OERKOP aims to understand and describe the mechanisms underlying the OER for co-catalyst modified hematite photoanodes, by using a correlative operando characterization approach at the nanoscale. OERKOP proposes a comparative study between two archetypal materials used as photoanodes: α-Fe₂O₃ and BiVO₄, both catalytically activated by oxyhydroxide catalysts (M-OOH, with M = Fe, Ni, Co, Cu, Zn). Surface kinetics and time stability during the oxidation will be systematically evaluated. We intend combining multi-scale and multi-selective techniques - scanning transmission X-ray microscopy (STXM) and scanning transmission electron microscopy (STEM). Both techniques will employ a common sample environment in a dedicated photoelectrochemical cell. Complementary DFT calculations will allow dissecting complex effects and determining the reaction priorities of different photocatalytic sites.

CONSORTIUM:

SPEC CEA, CNRS Univ. Paris-Saclay	Synchrotron SOLEIL	IPCMS Univ. de Strasbourg CNRS
Dana STANESCU (LNO) Yannick DAPPE (GMT) Cindy ROUNTREE (SPHYNX) Frederic MERLET (LNO)	Stefan STANESCU (HERMES) Jean-Baptiste BOY (HERMES) Karine CHAOUCHI (Laboratoire de chimie) Stephanie BLANCHANDIN (Laboratoire de chimie)	Ovidiu ERSEN Dris IHIAWAKRIM Walid BAAZIZ

POSITIONS:

PhD 1: estimated start date of the thesis: January 2024

M2 internship from February to July 2024:

We are looking for a motivated M2 student to fulfil the following missions:

Implementation and optimization of operando electrochemical STXM measurements;
Synthesis and photoelectrochemical characterization of photoanodes;
Physico-chemical characterization of photoanodes by SEM, XRD, Raman, STXM and XPEEM;
Data processing and analysis, writing of the internship report.

You can find more details here:

PhD 2: starting October 2024

Preliminary works and results:

Scanning transmission X-ray spectromicroscopy: a nanotool to probe hematite nanorods for solar water splitting, Stefan Stanescu, Dana Stanescu, Adam Hitchcock
- preprint March 2023 https://chemrxiv.org/engage/chemrxiv/articledetails/640de8d7b5d5dbe9e825c049;
- Journal of Electron Spectroscopy and Related Phenomena 265 (2023) 147334, https://doi.org/10.1016/j.elspec.2023.147334
Enhancement of the Solar Water Splitting Efficiency Mediated by Surface Segregation in Ti-doped Hematite Nanorods, Stanescu S, Alun T, Dappe YJ, Ihiawakrim D, Ersen O, Stanescu D.
- preprint February 2023 https://chemrxiv.org/engage/chemrxiv/article-details/643c03bc73c6563f14fae441
- ACS Appl. Mater. Interfaces 2023, https://doi.org/10.1021/acsami.3c02131
Characterizing surface states in hematite nanorod photoanodes, both beneficial and detrimental to solar water splitting efficiency, Dana Stanescu, Mekan Piriyev, Victoria Villard, Cristian Mocuta, Adrien Besson, Dris Ihiawakrim, Ovidiu Ersen, Jocelyne Leroy, Sorin G. Chiuzbaian, Adam P. Hitchcock, Stefan Stanescu, J. Mater. Chem. A, 2020, 8, 20513-20530, https://doi.org/10.1039/D0TA06524B; hal-02934466

Results dissemination during OERKOP:

Highlights:

2023 : Des matériaux simples et abondants pour une énergie future propre et efficace :

https://www.synchrotron-soleil.fr/fr/actualites/des-materiaux-simples-et-abondants-pour-une-energie-future-propre-et-efficace-0

https://iramis.cea.fr/spec/Phocea/Vie_des_labos/Ast/ast.php?t=fait_marquant&id_ast=3580

Oral and poster presentations

Léon Schmidt, Walid Baaziz, Dana Stanescu, Stefan Stanescu, Ovidiu Ersen, Correlative in situ microscopy study of photoanodes for solar water splitting (oral)

18^ème Colloque de la Société Française des Microscopies, 3 au 7 juillet 2023, Rouen (France)

Léon Schmidt, Walid Baaziz, Dana Stanescu, Stefan Stanescu, Ovidiu Ersen, Correlative in situ microscopy study of photoanodes used in solar water splitting applications (oral)

The 20th International Microscopy Congress (IMC20), September 10-15, 2023, Busan (Korea)

Scientific preprints and peer-review articles

Internship and PhD thesis

MEETINGS:

1) Kick-off meeting: Date: 20^th of April @SPEC

#3546 - Màj : 06/11/2023

• Institut Rayonnement Matière de Saclay • UMR 3680 - Service de Physique de l'Etat Condensé (SPEC)

• Laboratoire Nano-Magnétisme et Oxydes (LNO)

• Aqueous chemical growth of nanostructured oxide films • Banc de mesure de la photo-électrolyse de l’eau / spectroscopie d’impédance