In the context of catalysis, plasmonic sensors can be employed to monitor the progress of catalytic reactions. When a catalytic reaction occurs at the surface of a plasmonic material, it induces changes in the local refractive index. These changes alter the SPR conditions, which can be detected as shifts in the resonance wavelength or intensity. By analyzing these shifts, researchers can gain insights into the reaction mechanisms, kinetics, and the nature of intermediates and products.