Germania is an important glass material used in fiber optics due to exhibiting lower wavefront error relative to conventional silica glasses. Germania also presents promising applications as a dopant in additive manufacturing processes to fabricate novel free form optics with variable refractive index. Actualizing germania glass applications is currently limited by a lack of stable, amorphous, colloidal GeO2 precursors. This presentation describes novel approaches to controlling amorphous nanoparticle growth and stability using sugar alcohols (e.g., mannitol) as surfactants. Dynamic light scattering and transmission electron microscopy measurements comparing mannitol-germania sols to control germania sols have demonstrated the effectiveness of this approach in controlling particle growth at various sizes. FTIR spectroscopy has verified that particles grown in the presence of mannitol have remained amorphous. Further characterization is underway to understand the chemical and structural properties of the mannitol-capped germania colloids. Results from these fundamental studies will ultimately elucidate the interactions between sugar alcohols and amorphous GeO2 stability and enable the fabrication of novel optical materials.

Influence of mannitol on GeO2 colloid growth and stability

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.