Total electrification of large-scale nanophotonic arrays by frictional charges

Localized surface plasmon resonance (LSPR) of metallic nanostructures is a unique phenomenon that controls the light in sub-wavelength volumes and enhances the light–matter interactions. Traditionally, the excitation and measurement of LSPR require bulky external light sources, and efforts to scale down to nano-plasmonic devices have predominantly relied on the system's miniaturization and associated accessories. Addressing this, here we show the generation and detection of LSPR wavelength (λLSPR) shifts in large-area nanostructured Au surfaces using frictional charges generated by triboelectric surfaces. We observe a complex interplay of the localized surface plasmons with frictional charges via concurrent spectroscopic and triboelectric measurements undertaken for the detection of bioconjugation in the streptavidin–biotin complex. When subjected to multivariate principal component analysis, a strong correlation between the triboelectric peak-to-peak voltage output response and the λLSPR shift is observed. Furthermore, we reveal a landscape of the interfacial events involved in the electrical generation/detection of the LSPR by using theoretical models and surface characterization. The demonstrated concept of electrification of plasmon resonance thus provides the underlying basis for the subsequent development of self-powered nano-plasmonic sensors and opens new horizons for advanced nanophotonic applications.