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Abstract Raman scattering is performed on Fe3GeTe2(FGT) at temperatures from 8 to 300 K and under pressures from the ambient pressure to 9.43 GPa. Temperature‐dependent and pressure‐dependent Raman spectra are reported. The results reveal respective anomalous softening and moderate stiffening of the two Raman active modes as a result of the increase of pressure. The anomalous softening suggests anharmonic phonon dynamics and strong spin–phonon coupling. Pressure‐dependent density functional theory and phonon calculations are conducted and used to study the magnetic properties of FGT and assign the observed Raman modes,and. The calculations proved the strong spin–phonon coupling for themode. In addition, a synergistic interplay of pressure‐induced reduction of spin exchange interactions and spin–orbit coupling effect accounts for the softening of themode as pressure increases.
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Strain‐Dependent Activity‐Stability Relations in RuO 2 and IrO 2 Oxygen Evolution Catalysts
Abstract Strain engineering is an effective strategy in modulating activity of electrocatalysts, but the effect of strain on electrochemical stability of catalysts remains poorly understood. In this work, we combineab initiothermodynamics and molecular dynamics simulations to examine the role of compressive and tensile strain in the interplay between activity and stability of metal oxides considering RuOand IrOas exemplary catalysts. We reveal that although compressive strain leads to improved activity via the adsorbate‐evolving mechanism of the oxygen evolution reaction, even small strains should substantially destabilize these catalysts promoting dissolution of transition metals. In contrast, our results show that the metal oxides requiring tensile strain to promote their catalytic activity may also benefit from enhanced stability. Importantly, we also find that the detrimental effect of strain on electrochemical stability of atomically flat surfaces could be even greater than that of surface defects.
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- Award ID(s):
- 1941204
- PAR ID:
- 10479351
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemElectroChem
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2196-0216
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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