Iridium, the most widely used anode catalyst in proton exchange membrane water electrolysis (PEMWE), must be used minimally due to its high price and limited supply. However, reducing iridium loading poses challenges due to abnormally large anode polarization. Herein, we present an anode catalyst layer (CL) based on a one-dimensional iridium nanofiber that enables a high current density operation of 3 A cm at 1.86 V, even at an ultralow loading (0.07 mg cm). The performance is maintained even with a Pt coating-free porous transport layer (PTL) because our nanofiber CL circumvents the interfacial electron transport problem caused by the native oxide on the Ti PTL. We attribute this to the low work function and the low-ionomer-exposed surface of the nanofiber CL, which prevent the formation of Schottky contact at the native oxide interface. These results highlight the significance of optimizing the electronic properties of the CL/PTL interface for low-iridium-loading PEMWE.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acsnano.4c06373 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
University of Science and Technology of China, Division of Nanomaterials & Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, CHINA.
Electrolysis of carbon dioxide (CO2) in acid offers a promising route to overcome CO2 loss in alkaline and neutral electrolytes, but requires concentrated alkali cations (typical ≥3 M) to mitigate the trade-off between low pH and high hydrogen evolution reaction (HER) rate, causing salt precipitation. Here we report a strategy to resolve this problem by introducing tensile strain in a copper (Cu) catalyst, which can selectively reduce CO2 to valuable multicarbon products, particularly ethylene, in a pH 1 electrolyte with 1 M potassium ions. We find that the tension-strained Cu creates an electron-rich surface that concentrates diluted potassium ions, contributing to CO2 activation and HER suppression.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Forschungszentrum Jülich, Institute of Energy Technologies - Fundamental Electrochemistry (IET-1), Jülich, Germany.
The study of degradation behavior of electrocatalysts in an industrial context calls for rapid and efficient analysis methods. Optical methods like Raman spectroscopy fulfil these requirements and are thus predestined for this purpose. However, the iridium utilized in proton exchange membrane electrolysis (PEMEL) is Raman inactive in its metallic state.
View Article and Find Full Text PDFAlzheimers Res Ther
January 2025
Radiology Department, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China.
Background: The imbalance of glutamate (Glu) and gamma-aminobutyric acid (GABA) neurotransmitter system plays a crucial role in the pathogenesis of Alzheimer's disease (AD). Riluzole is a Glu modulator originally approved for amyotrophic lateral sclerosis that has shown potential neuroprotective effects in various neurodegenerative disorders. However, whether riluzole can improve Glu and GABA homeostasis in AD brain and its related mechanism of action remain unknown.
View Article and Find Full Text PDFDalton Trans
January 2025
Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.
The electrochemical proton reactivity of transition metal complexes has received intensive attention in catalyst research. The proton-coupled electron transfer (PCET) process, influenced by the coordination geometry, determines the catalytic reaction mechanisms. Additionally, the p value of a proton source, as an external factor, plays a crucial role in regulating the proton transfer step.
View Article and Find Full Text PDFNano Lett
January 2025
Interdisciplinary Graduate Program in Materials Science, Vanderbilt University, Nashville, Tennessee 37235, United States.
Permeance-selectivity trade-offs are inherent to polymeric membranes. In fuel cells, thinner proton exchange membranes (PEMs) could enable higher proton conductance and increased power density with lower area-specific resistance (ASR), smaller ohmic losses, and lower ionomer cost. However, reducing thickness is accompanied by an increase in undesired species crossover harming performance and long-term efficiency.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!