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We demonstrate that the corrosion of AISI 1045 medium carbon steel and pure aluminum can be quantified by the turn-off fluorescent sensor Phen Green-SK (PGSK) in ethanol-based solutions. We first evaluate the dependence of the chelation enhanced quenching of PGSK on iron and aluminum ion concentrations. Subsequently, we apply PGSK to examine the anodic dissolution of metal corrosion. The observed time-dependent PGSK-quenching quantifies the corrosion rates of two metals over 24 h of immersion in ethanol-based solutions. The PGSK-based quantification of corrosion is compared to scanning electron microscopy and electrochemical techniques, including open circuit potential and Tafel extrapolation. The corrosion rates calculated from PGSK-quenching and Tafel extrapolation are in agreement, and both indicate a decrease in corrosion rates over 24 h. Our work shows PGSK can efficiently sense and quantify anodic corrosion reactions at metal interfaces, especially in organic solvents or other non-aqueous environments where the application of electrochemical techniques can be limited by the poor conductivity of the surrounding medium. 

Chiral plasmonic surfaces with 3D “forests” from nanohelicoids should provide strong optical rotation due to alignment of helical axis with propagation vector of photons. However, such three-dimensional nanostructures also demand multi-step nanofabrication, which is incompatible with many substrates. Large-scale photonic patterns on polymeric and flexible substrates remain unattainable. Here, we demonstrate the substrate-tolerant direct-write printing and patterning of silver nanohelicoids with out-of-plane 3D orientation using circularly polarized light. Centimeter-scale chiral plasmonic surfaces can be produced within minutes using inexpensive medium-power lasers. The growth of nanohelicoids is driven by the symmetry-broken site-selective deposition and self-assembly of the silver nanoparticles (NPs). The ellipticity and wavelength of the incident photons control the local handedness and size of the printed nanohelicoids, which enables on-the-fly modulation of nanohelicoid chirality during direct writing and simple pathways to complex multifunctional metasurfaces. Processing simplicity, high polarization rotation, and fine spatial resolution of the light-driven printing of stand-up helicoids provide a rapid pathway to chiral plasmonic surfaces, accelerating the development of chiral photonics for health and information technologies.