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Assisted by predictions from density functional theory, we used infrared spectroscopy to observe hydride ions introduced into SrTiO3 crystals. 

Abstract The creation of metal‐metal oxide interfaces is an important approach to fine‐tuning catalyst properties through strong interfacial interactions. This article presents the work on developing interfaces between Pt and CeO_xthat improve Pt surface energetics for the hydrogen evolution reaction (HER) within an alkaline electrolyte. The Pt‐CeO_xinterfaces are formed by depositing size‐controlled Pt nanoparticles onto a carbon support already coated with ultrathin CeO_xnanosheets. This interface structure facilitates substantial electron transfer from Pt to CeO_x, resulting in decreased hydrogen binding energies on Pt surfaces, and water dissociation for the HER, as predicted by the density functional theory (DFT) calculations. Electrochemical testing indicates that both Pt specific activity and mass activity are improved by a factor of 2 to 3 following the formation of Pt‐CeO_xinterfaces. This study underscores the significance and potential of harnessing robust interfacial effects to enhance electrocatalytic reactions. 

Dipoles are ubiquitous, and their impacts on materials and interfaces affect many aspects o fdaily life. Despite their importance, dipoles remain underutilized, often because of insufficient knowledge about the structures producing them. As electrostatic analogues of magnets, electrets possess ordered electric dipoles. Here, we characterize the structural dynamics of bioinspired electret oligomers based on anthranilamide motifs. We report dynamics simulations, employing a force field that allows dynamic polarization, in a variety of solvents. The results show a linear increase in macrodipoles with oligomer length that strongly depends on solvent polarity and hydrogen-bonding (HB) propensity, as well as on the anthranilamide side chains. An increase in solvent polarity increases the dipole moments of the electret structures while decreasing the dipole effects on the moieties outside the solvation cavities. The former is due to enhancement of the Onager reaction field and the latter to screening of the dipole-generated fields. Solvent dynamics hugely contributes to the fluctuations and magnitude of the electret dipoles. HB with the solvent weakens electret macrodipoles without breaking the intramolecular HB that maintains their extended conformation. This study provides design principles for developing a new class of organic materials with controllable electronic properties.