Supramolecular Engineering of Vinylene-Linked Covalent Organic Framework - Ruthenium Oxide Hybrids for Highly Active Proton Exchange Membrane Water Electrolysis.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39901501.
- Also identified by DOI 10.1002/adma.202417374 and PMC identifier 11923516.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The controlled formation of a functional adlayer at the catalyst-water interface is a highly challenging yet potentially powerful strategy to accelerate proton transfer and deprotonation for ultimately improving the performance of proton-exchange membrane water electrolysis (PEMWE). In this study, the synthesis of robust vinylene-linked covalent organic frameworks (COFs) possessing high proton conductivities is reported, which are subsequently hybridized with ruthenium dioxide yielding high-performance anodic catalysts for the acidic oxygen evolution reaction (OER). In situ spectroscopic measurements corroborated by theoretical calculations reveal that the assembled hydrogen bonds formed between COFs and adsorbed oxo-intermediates effectively orient interfacial water molecules, stabilizing the transition states for intermediate formation of OER. This determines a decrease in the energy barriers of proton transfer and deprotonation, resulting in exceptional acidic OER performance. When integrated into a PEMWE device, the system achieves a record current density of 1.0 A cm<sup>-2</sup> at only 1.54 V cell voltage, with a long-term stability exceeding 180 h at industrial-level 200 mA cm<sup>-2</sup>. The approach relying on the self-assembly of an oriented hydrogen-bonded adlayer highlights the disruptive potential of COFs with customizable structures and multifunctional sites for advancing PEMWE technologies.