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1. Mechanistic insights into oxygen reduction reaction on metal/perovskite catalysts: Interfacial interactions and reaction pathways

   https://doi.org/10.1016/j.ssi.2025.116808  

   Li, Wenhao; Drozd, Vadym; Sozal, Md_Shariful_Islam; Li, Meng; Cheng, Zhe (March 2025, Solid State Ionics)

   The oxygen reduction reaction (ORR) is a critical process in energy conversion systems, influencing the efficiency and performance of various devices such as fuel cells, batteries, and electrolyzers. Perovskite-supported metal materials (metal/perovskite) offer several advantages as ORR electrocatalysts, including strong metal-support interactions, oxygen vacancy formation in the perovskite lattice, and synergistic triple-phase boundary (TPB) activity at the interface. Despite their significance, the mechanistic understanding of ORR on metal/perovskite catalysts remains incomplete, particularly at metal/perovskite interfaces. This study investigates ORR on BaZrO3 (BZO) perovskite-supported metal clusters (Pt or Ag) using density functional theory (DFT) to unravel critical insights into charge redistribution at the metal/BZO interface. Energy profiles for elemental steps along two different ORR pathways—oxygen adsorption on the metal cluster surface and direct oxygen adsorption at the TPB—were calculated to explore the effects of different active sites. The results provide a deeper understanding of ORR on metal/perovskite catalysts, emphasizing the role of interfacial interactions and pathway-dependent reaction mechanisms. This work paves the way for guiding the design of high-performance electrocatalysts for ORR in terms of composition, interface design, and local environment modification for a broad range of energy applications. 

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2. Differentiating Intra-Assembly and Interlayer Energy Transfer in Metal-Ion-Linked Molecular Multilayers

   https://doi.org/10.1021/acs.jpcc.4c04033  

   McLeod, Grace M; Nolder, Jackson; Arcidiacono, Ashley; Lindbom, Sarah; Dos_Santos, Nikolas R; Lambert, Ethan C; Ayad, Suliman; Beery, Drake; Alabugin, Igor V; Hanson, Kenneth (October 2024, The Journal of Physical Chemistry C)

   Metal-ion-linked molecular multilayers on metal oxide surfaces are promising for applications ranging from solar energy conversion to sensing. Most of these applications rely on energy and electron transfer between layers/molecules which can be envisioned to occur via intra-assembly (IA; between metal-ion-linked molecules) and interlayer (IL; between separate layers of nonlinked molecules) processes. Here, we describe our effort to differentiate between IL and IA energy transfer using a bilayer composed of ZrO2, a phosphonated anthracene derivative (A), a zinc(II) linking ion, and a Pt(II)porphyrin (P). Both time-resolved emission and transient absorption measurements show no impact of diluting the anthracene layer with a spectroscopically inert spacer on the rate of 1A* to P and 3P* to A, singlet, and triplet energy transfer, respectively. These results indicate that energy transfer within the metal-ion-linked assembly (i.e., ZrO2-A–Zn-P) is more rapid than with an adjacent, nonlinked A molecule, even for a P derivative capable of laying down on the surface. These insights are an important step toward structural design principles maximizing the efficiency/rate of energy transfer in multilayer assemblies. 

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3. The role of anions in adsorbate-induced anchoring transitions of liquid crystals on surfaces with discrete cation binding sites

   https://doi.org/10.1039/C7SM01981E  

   Szilvási, Tibor; Bao, Nanqi; Yu, Huaizhe; Twieg, Robert J.; Mavrikakis, Manos; Abbott, Nicholas L. (January 2018, Soft Matter)

   We report a combined theoretical and experimental effort to elucidate systematically for the first time the influence of anions of transition metal salt-decorated surfaces on the orientations of supported films of nematic liquid crystals (LCs) and adsorbate-induced orientational transitions of these LC films. Guided by computational chemistry predictions, we find that nitrate anions weaken the binding of 4′- n -pentyl-4-biphenylcarbonitrile (5CB) to transition metal cations, as compared to perchlorate salts, although binding is still sufficiently strong to induce homeotropic (perpendicular) orientations of 5CB. In addition, we find the orientations of the LC to be correlated across all metal cations investigated by a molecular anchoring energy density that is calculated as the product of the single-site binding energy and metal cation binding site density on the surface. The weaker single-site binding energy caused by nitrate also facilitates competitive binding of adsorbates to the metal cations, leading to more facile orientational transitions induced by adsorbates. Finally, our analysis suggests that nitrate anions recruit water via hydrogen bonding to the metal binding sites, modulating further the relative net binding energies of 5CB and adsorbates to surfaces decorated with metal nitrates. After accounting for the presence of water, we find a universal exponential relationship between the calculated displacement free energies and measured dynamic response of LCs to adsorbates for all metal salts studied, independent of the metal salt anion. 

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4. Förster resonance energy transfer in absorbing environment

   https://doi.org/10.1117/12.3027550  

   Petrosyan, Lyudvig S; Noginov, Mikhail A; Shahbazyan, Tigran V (October 2024, SPIE)

   Engheta, Nader; Noginov, Mikhail A; Zheludev, Nikolay I (Ed.)

   We present an analytical model for Förster resonance energy transfer between donors and acceptors in the presence of a metal surface. We find that energy transfer to the metal results in a reduction of the Förster radius, leading to a suppression of concentration quenching for high molecule concentrations. 

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5. Plasmonic catalysis with bi-resonant noble metal – CuFeS2 chalcopyrite hybrid structures

   https://doi.org/10.1088/1361-6528/add93f  

   Kundu, Koustav; Ouyang, Tianhong; Reinhard, Björn (May 2025, Nanotechnology)

   Both noble metal nanoparticles (NPs) and chalcopyrite (CuFeS2) nanocrystals (NCs) provide resonant absorption in the visible, albeit through different mechanisms. Coherent oscillations of free conduction band electrons give rise to localized plasmons in noble metal NPs, whereas collective oscillations of bound electrons are responsible for quasistatic resonances in CuFeS2 NCs. This manuscript reviews the photophysical and photocatalytic properties of both noble metal and chalcopyrite nanostructures as well as direct and indirect charge and energy transfer processes in hybrid structures containing noble metal NPs and either semiconductor NCs or molecular photosensitizers or photocatalysts. CuFeS2 NCs share structural similarities with conventional semiconductor NCs, but the availability of collective charge oscillations in the visible facilitates a resonant coupling to localized plasmons in NPs. Hybrid nanostructures containing both metal and chalcopyrite building blocks are examined as a platform for wavelength-dependent charge and energy transfer and bifunctional reactivity for enhanced plasmonic photocatalysis. 

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