Advanced electrochemical tools to characterise nano-electrocatalysts

ABSTRACT

The synthesis and physical characterization of (nano)catalyst materials is often done with atomic scale precision utilizing state-of-the-art techniques. Conversely, characterization of their electrocatalytic performance often relies on techniques that were developed more than a century ago and for much simpler systems, such as the classical Tafel analysis. This gap in the consideration level between material and electrochemical characterization limits our ability to design advanced nanomaterials for electrocatalysis and can be overcome by developing and utilizing advanced electrochemical methods. [1]
This will be exemplified for transition metal oxide catalysts, being highly promising catalysts for alkaline water splitting thanks to their relatively high abundance and high catalytic activity. Due to their limited electrical conductivity they are often used as nanoparticles and their catalytic performance is assessed based on experiments at composite electrodes. Besides the nanocatalyst of interest, these electrodes contain catalytically inactive binders and conductive additives. This makes it highly challenging – if not impossible – to distinguish influences of catalyst properties from matrix effects. For example, observed effects of particle morphology on electrocatalytic activity may simply originate from different wetting/blocking of catalyst active sites by the used additives or by different iR drop across the composite film, instead of signifying different charge transfer kinetics.
Single nanoparticle electrochemistry allows to overcome this limitation by studying electrocatalysis at individual nanoparticles [2]. Employing this approach, particle morphology-activity relations and support effects can be determined experimentally. These experiments can be linked to advanced theory data, thanks to the comparably small size of the single particle electrochemical system (Fig. 1.).
Complementary operando spectro-electrochemical investigations are equally essential for the design of non-precious-metal electrocatalysts, as these typically undergo substantial transformation, forming the catalytically active species only under operation conditions and converting back to less active species under ex situ conditions. [1,3] In this seminar we will discuss both, single entity electrochemistry and spectro-electrochemical approaches applied to nanoscale materials.
Figure 1: Single nanoparticle electrochemistry shows higher water oxidation activity for cobalt oxide cubes than spheres and sheds new light on catalyst-support interactions. [2].
References
[1] J. Linnemann, K. Kanokkanchana, K. Tschulik, ACS Catalysis, 11 (2021) 5318–5346.
[2] Z. Liu, H. M.A. Amin, Y. Peng, M. Corva, R. Pentcheva, K. Tschulik, Adv. Funct. Mater., 1 (2023) 2210945
[3]. C. Luan, J. Angona, A. Bala Krishnan, M. Corva, P. Hosseini, M. Heidelmann, U. Hagemann, E. Batsa Tetteh, W. Schuhmann, K. Tschulik, T. Li, Angew. Chem., Int. Ed. (2023), 62, e202305982.

BIO

Career

06/2018 – ongoing

Professor and Chairholder of the Chair of Analytical Chemistry II – Electrochemistry & Nanoscale Materials at the RUB

2023 – ongoing

Visiting Professor at CEITEC, Brno Univer-sity, Czech Republic

2021 – ongoing

Scientific director of the chemistry specific incubator Start4Chem

09/2015 – 05/2018

Junior Professor for Micro- & Nanoelectrochemistry at the RUB

03/2017 – 05/2017

Invited visiting professorship at Université Paris Diderot, Paris, Fr

11/2013 – 12/2013

Research stay at MINTEK, Johannesburg, South Africa (Dr. Robert Tshikhudo)

11/2012 – 08/2015

Post-Doc and Marie Curie Intra European Fellow at the University of Oxford (UK)
RG Prof. Richard Compton

04/2012 – 11/2012

Post-Doc at the Leibniz Institute für Festkörper- und Werkstoffforschung (IFW) Dresden
RG Prof. Jürgen Eckert

04/2012

Promotion to Dr. rer. nat. at the TU Dresden (summa cum laude)

05/2010 – 08/2010

Research stay at the University of Virginia, Charlottesville, USA (Prof. Giovanni Zangari)

08/2008 – 03/2012

Doctoral Candidate at the IFW Dresden, Institut für Metallische Werkstoffe
RG Prof. Ludwig Schultz

10/2003 – 05/2008

Diploma Programme Chemistry at the TU Dresden, Diploma at the RG Prof. Michael Ruck

Awards and Prices

2021

Fellow of the Max-Planck-Gesellschaft (MPI for Sustainable Materials)

07/2020

ERC Starting Grant of the European Research Council

05/2020

Elected member of the NRW-Academy of Sciences, Humanities and the Arts

05/2018

„Hellmuth-Fischer medal“ of the DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V.

2017

Early Career Analytical Electrochemistry Prize of the International Society of Electrochemistry Division 1

09/2016

„Joachim Walter Schultze-Preis“ of the Arbeitsgemeinschaft Elektrochemischer Forschungsinstitutionen e.V. (AGEF)

10/2014

„NRW Rückkehrerprogramm zur Förderung der Rückkehr des hoch-qualifizierten Forschungsnachwuchses aus dem Ausland“ of the state NRW

06/2013 – 05/2015

„Marie Curie Intra European Fellowship for Career Development“ of the EU

11/2013

„Nachwuchspreis der Leibniz-Gemeinschaft“ in the category of Natural and Technical Sciences

10/2013

„Deutsche-Bank-Nachwuchspreis“ of the IFW Dresden

07/2012

„Förderpreis auf dem Gebiet der Angewandten Elektrochemie“ of the Gesellschaft Deutscher Chemiker (GDCh)

05/2009 – 11/2011

„Promotionsstipendium“ of the Studienstiftung des deutschen Volkes

12/2008

„Lohrmann Medaille“ of the TU Dresden for the best graduate of the year

Publications

>180 Publications in peer-review journals