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DOE OSTI · 3016132

Time-resolved electrical potential pump – X-ray photoelectron spectroscopy probe developments for investigating dynamic processes occurring at electrochemical interfaces

Mahl, Johannes [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000309898665)·Gokturk, Pinar Aydogan [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Koc Univ., Istanbul (Turkey)] (ORCID:0000000182698884)·Hamlyn, Rebecca [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000167716693)·English, Damon [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0009000934542389)·Suzer, Sefik [Bilkent University, Ankara (Turkey)] (ORCID:0000000258662600)·Qian, Jin [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)]·Crumlin, Ethan J. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:000000033132190X)
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Abstract

Electrode–electrolyte interfaces are of critical importance in several fields, including renewable energy, corrosion, and environmental chemistry. However, investigating these interfaces under operational conditions poses considerable challenges due to the limitations of the instrumentation employed. While recent advancements in in situ and operando techniques have enhanced our comprehension of the steady-state properties of solid-liquid interfaces, the dynamic behaviors of these systems remain inadequately explored. This study introduces a time-resolved X-ray photoelectron spectroscopy (XPS) technique designed to capture transient reaction intermediates and charging dynamics at electrified interfaces. The presented proof-of-principle study demonstrates that electrochemical processes, represented by an equivalent electrical circuit (EEC) model, can be probed and understood using square wave voltage pulses of a potentiostat synchronized to the modified data acquisition of an XPS setup. This method offers a valuable alternative to traditional pump–probe techniques, facilitating the investigation of a broader range of electrochemical systems. A dedicated software package for analyzing time- and energy-resolved XPS with a focus on extracting parameters of the EEC is geared towards benchmarking different EECs in future real-world electrochemical experiments.

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ElectrochemistryEquivalent electrical circuitOperandoPump–probeTime-resolvedXPS

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Mahl, Johannes [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000309898665), Gokturk, Pinar Aydogan [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Koc Univ., Istanbul (Turkey)] (ORCID:0000000182698884), Hamlyn, Rebecca [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000167716693), English, Damon [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0009000934542389), Suzer, Sefik [Bilkent University, Ankara (Turkey)] (ORCID:0000000258662600), Qian, Jin [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)], Crumlin, Ethan J. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:000000033132190X). 2025-07-29. Time-resolved electrical potential pump – X-ray photoelectron spectroscopy probe developments for investigating dynamic processes occurring at electrochemical interfaces. https://doi.org/10.1016/j.apsusc.2025.164185

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