e-space
Manchester Metropolitan University's Research Repository

    Supported Oxygen Evolution Catalysts by Design: Toward Lower Precious Metal Loading and Improved Conductivity in Proton Exchange Membrane Water Electrolyzers

    Regmi, Yagya N, Tzanetopoulos, Eden, Zeng, Guosong, Peng, Xiong, Kushner, Douglas I, Kistler, Tobias A, King, Laurie A and Danilovic, Nemanja (2020) Supported Oxygen Evolution Catalysts by Design: Toward Lower Precious Metal Loading and Improved Conductivity in Proton Exchange Membrane Water Electrolyzers. ACS Catalysis, 10 (21). pp. 13125-13135. ISSN 2155-5435

    [img]
    Preview
    Accepted Version
    Available under License In Copyright.

    Download (5MB) | Preview

    Abstract

    Reducing the precious metal content of water oxidation catalysts for proton-exchange-membrane water electrolyzers remains a critical barrier to their large-scale deployment. Herein, we present an engineered architecture for supported iridium catalysts, which enables decreased precious metal content and improved activity and conductivity. The improvement in performance at lower precious metal loading is realized by the deposition of a conformal layer of platinum nanoparticles on titanium dioxide (TiO2) using a facile photoreduction method to prepare conductive layer coated supports (CCSs). Platinum nanoparticles are homogeneously dispersed on TiO2, and the conductivity of the subsequent catalysts with 39 wt % precious group metal loadings is significantly higher than the commercial 75 wt % loaded IrO2-TiO2 catalysts. The conformal conductive layer also maintains an enhanced conductivity and electrochemical activity upon thermal annealing when compared to catalysts without the conductive layer and nonconformal heterogeneous conductive layer. The iridium mass activity from half-cell studies shows a 141% improvement for CCS supported catalysts at 42% lower loadings compared to the commercial catalysts. The conductive layer also improves the single cell electrolyzer performance at a similar catalyst loading in comparison to a commercial state-of-the-art catalyst. We correlate the physical properties of the engineered catalysts with their electrochemical performance in electrolyzers to understand structure–activity relationships, and we anticipate further performance improvements upon synthesis and materials optimizations.

    Impact and Reach

    Statistics

    Activity Overview
    6 month trend
    862Downloads
    6 month trend
    344Hits

    Additional statistics for this dataset are available via IRStats2.

    Altmetric

    Repository staff only

    Edit record Edit record