Electrospun Pt Nanowires as a Highly Conductive Support for Ir for the Electrochemical Oxygen Evolution Reaction
Authors: O'Carroll Tom , Diaz-Abad Sergio , Wu Gang , Komini Babu Siddharth , Wang Xiaojing , Spendelow Jacob S. 
Published: December 2024

The electrochemical Oxygen Evolution Reaction (OER) is a critically important reaction towards realizing a sustainable energy economy through the utilization of hydrogen as an environmentally friendly fuel. However, the relatively low conductivity of conventional IrOx catalysts hinders their performance and necessitates use of high Ir loadings.[1, 2] To counteract this insufficiency, utilizing highly conductive catalyst layer supports has become an effective strategy for maintaining optimal conductivity.[3-7] While they have allowed for improved stability, TiO2-based fibers typically possess poor conductivity. Thus, the inclusion of an additional components (Pt, Nb, Au, etc.) has been shown to improve the catalyst layer conductivity, thereby enhancing the OER activity for this class of catalyst.[8, 9] Herein, we utilize electrospinning as a method for producing conductive Pt-based nanowires with customizable porosity and diameter on the scale of tens of nanometers to be utilized as a support for active Ir-based catalysts. By controlling the electrospinning solution and operating parameters, the characteristics of as-spun Pt-CNFs may be controlled before high-temperature treatment to obtain Pt-NWs with regulated diameter.[10] Following the fabrication of Pt-NWs, we analyze the electrochemical performance and properties of the resulting Ir@Pt-NWs electrocatalyst.

Acknowledgment

Financial support from the Laboratory Directed Research and Development Program at Los Alamos National Laboratory through project 20240061DR is gratefully acknowledged.

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