idw – Informationsdienst Wissenschaft

Nachrichten, Termine, Experten

Grafik: idw-Logo
Science Video Project
idw-Abo

idw-News App:

AppStore

Google Play Store



Instance:
Share on: 
06/17/2020 11:51

Al2Pt for oxygen evolution reaction in water splitting: a strategy for creating multi-functionality in electrocatalysis

Dipl.-Übers. Ingrid Rothe Presse- und Öffentlichkeitsarbeit
Max-Planck-Institut für Chemische Physik fester Stoffe

    The inter-institutional MPG-consortium MAXNET Energy integrated the scientists from different institutions in Germany and abroad. As a result of close and fruitful collaboration within this framework, the scientists from Chemical Metal Science department at MPI CPfS together with experts from Fritz Haber Institute in Berlin and MPI CEC in Mülheim an der Ruhr, developed a new concept for producing multifunctionality in electrocatalysis and successfully illustrated it with an example of intermetallic compound Al2Pt as precursor for OER electrocatalyst material.

    The transition from fossil fuels to renewable energy sources strongly depends on an availability of effective systems for energy conversion and storage. Considering hydrogen as a carrier molecule, proton exchange membrane electrolysis offers numerous advantages, like operation at high current densities, low gas crossover, compact system design etc. However, its wide implementation is hindered by slow kinetics of oxygen evolution reaction (OER), enhancement of which requires the application of low-abundant and expensive Ir-based electrocatalysts. Looking for rational design of new types of OER electrocatalysts and addressing fundamental questions about the key reactions in energy conversion, the inter-institutional MPG-consortium MAXNET Energy integrated the scientists from different institutions in Germany and abroad. As a result of close and fruitful collaboration within this framework, the scientists from Chemical Metal Science department at MPI CPfS together with experts from Fritz Haber Institute in Berlin and MPI CEC in Mülheim an der Ruhr, developed a new concept for producing multifunctionality in electrocatalysis and successfully illustrated it with an example of intermetallic compound Al2Pt as precursor for OER electrocatalyst material.
    Intermetallic compound Al2Pt (anti-CaF2 type of crystal structure) combines two characteristics important for electrocatalytic performance: (i) reduced density of states at the Fermi level of Pt, and (ii) pronounced charge transfer from aluminium towards platinum, leading to strongly polar chemical bonding in this compound (Figure 1). These features provide inherent OER activity (Figure 2) and increasing stability against complete oxidation under harsh oxidative conditions of OER. Upon OER conditions, Al2Pt undergoes restructuring in the near-surface region as a result of the self-controlled dissolution of aluminium (inset of Figure 2). The roughness and porosity of in situ-formed near-surface microstructure allow to compensate the specific activity loss. Even after exceptionally long stability experiment (19 days) at high current densities (90 mA cm-2) the bulk material retains its structural and compositional integrity. Extending the choice of synthesis techniques, e.g. thin films growth, and exploring the variety of intermetallic compounds draw the main guidelines for future development of the proposed strategy.

    The research at the Max Planck Institute for Chemical Physics of Solids (MPI CPfS) in Dresden aims to discover and understand new materials with unusual properties.
    In close cooperation, chemists and physicists (including chemists working on synthesis, experimentalists and theoreticians) use the most modern tools and methods to examine how the chemical composition and arrangement of atoms, as well as external forces, affect the magnetic, electronic and chemical properties of the compounds.
    New quantum materials, physical phenomena and materials for energy conversion are the result of this interdisciplinary collaboration.
    The MPI CPfS (www.cpfs.mpg.de) is part of the Max Planck Society and was founded in 1995 in Dresden. It consists of around 280 employees, of which about 180 are scientists, including 70 doctoral students.


    Contact for scientific information:

    Iryna Antonyshyn, Yuri Grin


    Original publication:

    Iryna Antonyshyn, Ana M. Barrios Jiménez, Olga Sichevych, Ulrich Burkhardt, Igor Veremchuk, Marcus Schmidt, Alim Ormeci, Ioannis Spanos, Andrey Tarasov, Detre Teschner, Gerardo Algara-Siller, Robert Schlögl, Yuri Grin, Al2Pt for oxygen evolution reaction in water splitting: a strategy for creating multi-functionality in electrocatalysis, Angew. Chem. Int. Ed., accepted,
    DOI: 10.1002/anie.202005445.


    More information:

    https://www.cpfs.mpg.de/3208704/20200608


    Images

    Atomic QTAIM basins of platinum and aluminium (transparent) and Al-Pt bond basin (red) in the Al2Pt compound, revealing the pronounced charge transfer from Al to Pt atoms and polar character of Al-Pt atomic interactions.
    Atomic QTAIM basins of platinum and aluminium (transparent) and Al-Pt bond basin (red) in the Al2Pt ...

    © MPI CPfS

    Long-term OER experiment in 0.1 M HClO4 with Al2Pt anode, expressed via series of linear sweep voltammetry curves, recorded after every 24h of chronopotentiometry at 90 mA cm-2. Inset: EDX spectrum image of the top 1.2 mm of the sample after the long-term
    Long-term OER experiment in 0.1 M HClO4 with Al2Pt anode, expressed via series of linear sweep volta ...

    © MPI CPfS


    Criteria of this press release:
    Business and commerce, Journalists, Students
    Chemistry, Energy, Environment / ecology, Physics / astronomy
    transregional, national
    Research results, Scientific Publications
    English


     

    Atomic QTAIM basins of platinum and aluminium (transparent) and Al-Pt bond basin (red) in the Al2Pt compound, revealing the pronounced charge transfer from Al to Pt atoms and polar character of Al-Pt atomic interactions.


    For download

    x

    Long-term OER experiment in 0.1 M HClO4 with Al2Pt anode, expressed via series of linear sweep voltammetry curves, recorded after every 24h of chronopotentiometry at 90 mA cm-2. Inset: EDX spectrum image of the top 1.2 mm of the sample after the long-term


    For download

    x

    Help

    Search / advanced search of the idw archives
    Combination of search terms

    You can combine search terms with and, or and/or not, e.g. Philo not logy.

    Brackets

    You can use brackets to separate combinations from each other, e.g. (Philo not logy) or (Psycho and logy).

    Phrases

    Coherent groups of words will be located as complete phrases if you put them into quotation marks, e.g. “Federal Republic of Germany”.

    Selection criteria

    You can also use the advanced search without entering search terms. It will then follow the criteria you have selected (e.g. country or subject area).

    If you have not selected any criteria in a given category, the entire category will be searched (e.g. all subject areas or all countries).