Effects of para-substituents of styrene derivatives on their chemical reactivity on platinum nanoparticle surfaces

摘要: Stable platinum nanoparticles were successfully prepared by the self-assembly of para-substituted styrene derivatives onto surfaces as a result platinum-catalyzed dehydrogenation and transformation vinyl groups to acetylene ones, forming platinum–vinylidene/–acetylide interfacial bonds. Transmission electron microscopic measurements showed that well dispersed without apparent aggregation, suggesting sufficient protection organic capping ligands, average core diameter was estimated be 2.0 ± 0.3 nm, 1.3 0.2 1.1 nm for capped with 4-tert-butylstyrene, 4-methoxystyrene, 4-(trifluoromethyl)styrene, respectively, decreasing rate increasing Taft (polar) constant para-substituents. Importantly, resulting exhibited unique photoluminescence, where an increase Hammett para-substituents corresponded blue-shift photoluminescence emission, enlargement HOMO–LUMO band gap nanoparticle-bound moieties. Furthermore, electrocatalytic activity towards oxygen reduction in acidic media, best performance among series samples observed 4-tert-butylstyrene-capped due optimal combination nanoparticle size ligand effects on bonding interactions between species.