DFT-Based Approach Enables Deliberate Tuning of Alloy Nanostructures Plasmonic Properties

<div>Using DFT we calculated band structures and dielectric functions of multiple binary alloy systems. The obtained data enabled us to elucidate the interconnection between alloy composition, fundamental properties such as band structure and their optical properties. The analysis provides the explanation for the smooth change of optical properties in the UV/VIS range and reveals the appearance of strong optical losses in the IR range due to interband transitions. Since they are present in all alloys but not in pure metals we identify such transitions as an emergent property of alloying. To predict plasmonic properties of different alloy nanostructures we performed electrodynamics simulations based on calculated and experimental dielectric functions. The results showed that that calculations based on the standardly used PBE functional in some cases drastically deviate from experiment-based results, and the calculations with an equally efficient GLLB-SC functional are superior. <br></div>

DFT-Based Approach Enables Deliberate Tuning of Alloy Nanostructures Plasmonic Properties

<div>Using DFT we calculated band structures and dielectric functions of multiple binary alloy systems. The obtained data enabled us to elucidate the interconnection between alloy composition, fundamental properties such as band structure and their optical properties. The analysis provides the explanation for the smooth change of optical properties in the UV/VIS range and reveals the appearance of strong optical losses in the IR range due to interband transitions. Since they are present in all alloys but not in pure metals we identify such transitions as an emergent property of alloying. To predict plasmonic properties of different alloy nanostructures we performed electrodynamics simulations based on calculated and experimental dielectric functions. The results showed that that calculations based on the standardly used PBE functional in some cases drastically deviate from experiment-based results, and the calculations with an equally efficient GLLB-SC functional are superior. <br></div>

Synthesis of Bimetallic PdAg Nanoparticles and Their Electrocatalytic Activity toward Ethanol

Palladium-based bimetallic nanoparticles (NPs) have been studied as important electrocatalysts for energy conversion due to their high electrocatalytic performance and the less usage of the noble metal. Herein, well-dispersed PdAg NPs with uniform size were prepared via oil bath accompanied with the hydrothermal method. The variation of the Ag content in PdAg NPs changed the lattice constant of the face-centered cubic alloy nanostructures continuously. The Pd/Ag molar ratio in the PdAg alloy NPs affected their size and catalytic activity toward ethanol electrooxidation. Experimental data showed that PdAg NPs with less Ag content exhibited better electrocatalytic activity and durability than pure Pd NPs owing to both the small size and the synergistic effect. PdAg-acac-4 with the Pd/Ag molar ratio of 4 : 1 in the start system possessed the highest catalytic current density of 2246 mA/mg for the electrooxidation of ethanol. The differences in the morphology and electrocatalytic activity of the as-made PdAg NPs have been discussed and analyzed.