Tricomponent Multiblock Nanorods for Fourier Transform Surface Plasmon Resonance and Its Chemical Sensing

In this study, we report a new mode of chemical sensing using Fourier transform surface plasmon resonance with tricomponent nanorods (Au, Ni, and Pt). By applying an external magnetic field, magnetically responsive multiblock nanorods fluctuate periodically, producing sigmoidal optical responses that are represented as a dominant frequency peak after Fourier transform conversion. Adding H₂O₂ to the solution under an external magnetic field perturbed the periodic nanorod rotation due to a catalytic reaction between the Pt segment and H₂O₂, which produces catalytic random fluctuation states. The target chemicals were detected by measuring the frequency domain recovery time between two competing states, the magnetic dominant state and the catalytic random state. These two states can be controlled and maximized by nanorod block design, demonstrating the effectiveness of our chemical sensing design using Fourier transform surface plasmon resonance.