Electrochemical Investigation of Porosity in Core–Shell Magnetoplasmonic Nanoparticles

Abstract

Porous core−shell nanoparticles (NPs) have emerged as a promising material for broad ranges of applications in catalysts, material chemistry, biology, and optical sensors. Using a typical Ag core−Fe 3 O 4 shell NP, a.k.a., magnetoplasmonic (MagPlas) NP, two porous shell models were prepared: i.e., Ag@Fe 3 O 4 NPs and its SiO 2 -covered NPs (Ag@Fe 3 O 4 @SiO 2 ). We suggested using cyclic voltammetry (CV) to provide unprecedented insight into the porosity of the core− shell NPs caused by the applied potential, resulting in the selective redox activities of the core and porous shell components of Ag@Fe 3 O 4 NPs and Ag@Fe 3 O 4 @SiO 2 NPs at different cycles of CV. The porous and nonporous core−shell nanostructures were qualitatively and quantitatively determined by the electrochemical method. The ratio of the oxidation current peak (μA) of Ag to Ag + in the porous shell to that in the SiO 2 coated (nonporous) shell was 400:3.2. The suggested approach and theoretical background could be extended to other types of multicomponent NP complexes.

Rugged Forest Morphology of Magnetoplasmonic Nanorods that Collect Maximum Light for Photoelectrochemical Water Splitting

“…[34,42] The LSV measurements were carried out on the NAFO NRs prepared to utilize drop casting (DC) techniques to obtain their effective OER catalytic activity with a low overpotential of current density. [43] The results of these measurements are presented in Figure S9a, Supporting Information. The corresponding Tafel slope of the drop-casting method exhibited the minor Tafel slope of 67 mV dec −1 , as shown in Figure S9b, Supporting Information.…”