Amorphous Si₃B₃N₇ Ceramic as a Versatile Host for Inorganic Phosphor Activators

Among the inorganic phosphors used in advanced lighting technologies, rare‐earth doped nitridosilicates have attracted significant attention because they exhibit superior photoluminescence properties in connection with high thermal, chemical, and mechanical stabilities. All of these materials are crystalline, which imposes substantial limitations in discovering new phosphors, since the activators to be included in the host matrix need to comply closely with the respective lattice sites, at least with respect to charge and size. As an approach to overcome such implications, an amorphous matrix, namely Si₃B₃N₇, is suggested as a universal nitride‐based host accessible to (co)dope various activators, e.g., Eu²⁺, Ce³⁺ and Tb³⁺. Unlike crystalline phosphors, in the amorphous Si₃B₃N₇ matrix, activator ions do not replace any atom from the random network host; instead, they act as network modifiers. The synthesis of this new class of amorphous phosphors is based on a precursor route, enabling high purities, and avoiding harsh temperature treatments.