Photo-Thermo-Refractive Glasses Doped with Silver Molecular Clusters as Luminescence Downshifting Material for Photovoltaic Applications

Silver nanostructures, including molecular clusters and plasmonic nanoparticles, attract much attention due to their unique optical properties and potential applications in various fields. Glasses doped with silver molecular clusters are known to possess bright luminescence under UV excitation, which opens up prospects of using the glasses as solar spectral converters to overcome poor spectral response for most of photovoltaic cells in the short-wavelength region. In this study, silver molecular clusters are formed in photo-thermo-refractive glass matrix both by UV irradiation and by Na+↔Ag+ion exchange and optically characterized. Photo-thermo-refractive glasses doped with silver molecular clusters, independently on silver introduction method, are shown to demonstrate broad absorption in the UV, intense white emission under excitation at 360 nm, and high photoluminescence quantum yield that meet requirements for luminescence downshifting materials. Despite this, only photo-thermo-refractive glass with silver molecular clusters uniformly distributed in the glass volume enhances the output power of a silicon photovoltaic cell, thus showing the potential for future application of photo-thermo-refractive glasses in photovoltaics, particularly in case of further experiments.