Au and Co₃O₄ anchored Bi₂WO₆ with enhanced electron paramagnetic resonance, surface plasmon resonance, nonlinear and magnetic properties

Abstract

The combination of surface plasmon resonance (SPR) effect with hetero‐p–n structure shows promising benefits to optical linear and nonlinear properties. In this study, Au nanoparticles (NPs) decorated p–n hetero‐structured Co3O4/Bi2WO6 composite was synthesized and characterized in terms of the optical linear and nonlinear and magnetic properties, morphology, electron transition, charge transfer, energy band gap, polarizability, SPR effect, and oxygen vacancies using scanning electron microscopy, X‐ray photoelectron spectroscopy, electron paramagnetic resonance spectroscopy, Z‐scan, ultraviolet–visible spectra, and vibrating sample magnetometer. The combination of Co3O4 provided active 3d electrons transition and charge transfer which increased carriers’ concentration and reduced the energy band gap. Au SPR enhanced the internal polarization and strengthened the built‐in electric field, yielding strong nonlinear behavior. In addition, magnetic Co3O4 endowed sample with room‐temperature ferromagnetism which was obviously strengthened by Au NPs. The obtained sample is promising for laser and photonics applications.