Silicate Glasses with Unprecedented High Nitrogen and Electropositive Metal Contents Obtained by Using Metals as Precursors

Oxonitridosilicate glasses, with high contents of nitrogen and electropositive metals, have been prepared by a novel synthesis route using metals as precursors (see Figure). They demonstrate high refractive indices, up to 2.30, and Vickers hardness values, up to 13.3 GPa, which are the highest values reported for any silicate glass. They constitute a significant extension of silicate glass compositions and are chemically flexible.