Tuning assembly of Ni-doped Au@FexOy magnetoplasmonic nanowires for optimizing photochemical water splitting

Abstract

The design of the particular geometric electrodes in photo-electrocatalysis is of significant importance to directly influence their catalytic performance. In this study, we have synthesized Ni-doped Au@FexOy magnetoplasmonic nanowires (MagPlas NWs) and leveraged diverse orientations of magnetic flux to disclose the active surfaces of the nanowire arrays incorporated into the electrode framework, thereby bringing to light active surface areas that facilitate adsorption of photons. Subjecting the Ni-Au@FexOy MagPlas NWs to magnetic fields at various orientations affects their light absorption intensity. The transverse mode exhibits impressive visible light absorption, which significantly increases its photocatalytic performance in oxygen evolution reaction (OER). The rugged forest shape array possesses remarkable visible light absorption, enhanced 2.01 mA cm−2 at 1.23 V vs. a reference hydrogen electrode (RHE), and long-term stability. The enhanced photoactivity is attributed to higher specific surface porosity and tuning of the magnetic field orientation to modulate the absorbance properties of the NWs.