Kinetics and direct imaging of electrochemically formed palladium hydride for efficient hydrogen evolution reaction

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Camuti, Luca, Kim, Se-Ho, Podjaski, Filip, Vega-Paredes, Miquel, Mingers, Andrea M., Acarturk, Tolga, Starke, Ulrich, Lotsch, Bettina V., Scheu, Christina, Gault, Baptiste, Zhang, Siyuan
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866913756543451136
author Camuti, Luca
Kim, Se-Ho
Podjaski, Filip
Vega-Paredes, Miquel
Mingers, Andrea M.
Acarturk, Tolga
Starke, Ulrich
Lotsch, Bettina V.
Scheu, Christina
Gault, Baptiste
Zhang, Siyuan
author_facet Camuti, Luca
Kim, Se-Ho
Podjaski, Filip
Vega-Paredes, Miquel
Mingers, Andrea M.
Acarturk, Tolga
Starke, Ulrich
Lotsch, Bettina V.
Scheu, Christina
Gault, Baptiste
Zhang, Siyuan
contents Active and reliable electrocatalysts are fundamental to renewable energy technologies. PdCoO2 has recently been recognized as a promising catalyst template for the hydrogen evolution reaction (HER) in acidic media thanks to the formation of active PdHx. In this article, we monitor the transformation of single PdCoO2 particles during HER, and confirm their almost complete transformation to PdHx with sub-millimeter depths and cracks throughout the particles. Using operando mass spectrometry, Co dissolution is observed under reductive potentials, leading to PdHx formation, whereas the dissolution partial current is found to be 0.1 % of the HER current. The formation of PdHx is confirmed through secondary ion mass spectrometry and quantitatively analyzed by atom probe tomography, enabled by isotope labelling of hydrogen using heavy water. Despite dry storage and high vacuum during sample preparations, an overall composition of PdD0.28 is measured for the PdHx sample, with separation between alpha- (D-poor) and beta- (D-rich) PdHx phases. The PdHx phase formed on PdCoO2 particles is stable for a wide electrochemical potential window, until Pd dissolution is observed at open circuit potentials. Our findings highlight the critical role of a templated growth method in obtaining stabilized PdHx, enabling efficient HER without the commonly slow activation processes observed in Pd. This offers insights into the design of more efficient electrocatalysts for renewable energy technologies.
format Preprint
id arxiv_https___arxiv_org_abs_2503_19040
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Kinetics and direct imaging of electrochemically formed palladium hydride for efficient hydrogen evolution reaction
Camuti, Luca
Kim, Se-Ho
Podjaski, Filip
Vega-Paredes, Miquel
Mingers, Andrea M.
Acarturk, Tolga
Starke, Ulrich
Lotsch, Bettina V.
Scheu, Christina
Gault, Baptiste
Zhang, Siyuan
Chemical Physics
Active and reliable electrocatalysts are fundamental to renewable energy technologies. PdCoO2 has recently been recognized as a promising catalyst template for the hydrogen evolution reaction (HER) in acidic media thanks to the formation of active PdHx. In this article, we monitor the transformation of single PdCoO2 particles during HER, and confirm their almost complete transformation to PdHx with sub-millimeter depths and cracks throughout the particles. Using operando mass spectrometry, Co dissolution is observed under reductive potentials, leading to PdHx formation, whereas the dissolution partial current is found to be 0.1 % of the HER current. The formation of PdHx is confirmed through secondary ion mass spectrometry and quantitatively analyzed by atom probe tomography, enabled by isotope labelling of hydrogen using heavy water. Despite dry storage and high vacuum during sample preparations, an overall composition of PdD0.28 is measured for the PdHx sample, with separation between alpha- (D-poor) and beta- (D-rich) PdHx phases. The PdHx phase formed on PdCoO2 particles is stable for a wide electrochemical potential window, until Pd dissolution is observed at open circuit potentials. Our findings highlight the critical role of a templated growth method in obtaining stabilized PdHx, enabling efficient HER without the commonly slow activation processes observed in Pd. This offers insights into the design of more efficient electrocatalysts for renewable energy technologies.
title Kinetics and direct imaging of electrochemically formed palladium hydride for efficient hydrogen evolution reaction
topic Chemical Physics
url https://arxiv.org/abs/2503.19040