Advanced optical waveguide design <i>via</i> encapsulation of 2,4,6-triphenylpyrylium chloride in oxide glasses

Pyrylium ion (C₅H₅O⁺)-based salts exhibit distinctive optical properties that can be tuned by external stimuli such as temperature and pressure, making them suitable materials for various nanoscale optoelectronic applications. However, their practical use has been limited by their solid powder form, which poses challenges for integration into realistic devices. Herein, we present a low-temperature, post-melting encapsulation method for the incorporation of a 2,4,6-triphenylpyrylium chloride salt within transparent phosphate glasses containing dispersed silver nanoparticles. This synthesis approach enables spatially controlled vitrification of high-refractive index pyrylium pathways within the glass matrix. The encapsulated salt retains its structural and optical properties, while the presence of randomly dispersed silver nanoparticles enhances light transmission upon scattering effects. The resulting pyrylium salt-glass composites exhibit robust waveguiding characteristics, positioning this technique as a promising route for the fabrication of advanced nano-engineered optoelectronic devices.