Papers

Tellurium dioxide (TeO2) based glasses have emerged as one of the most promising inorganzic, binderfree host matrices for rare-earth (RE) doped phosphors intended for white light-emitting diode (WLED) applications. Their low maximum phonon energy, high linear refractive index, wide optical transparency window, and good rare-earth ion solubility distinguish them favourably from conventional silicate, borate, and phosphate glass formers. This review critically surveys the literature on the synthesis, structure, and luminescence of Eu3+ (red), Tb3+ (green), and Dy3+ (blue/yellow) doped tellurite glasses, situating this body of work within the broader context of solid-state lighting and phosphor-converted LED research. The structural chemistry of the TeO2 network, the Judd–Ofelt framework used to quantify radiative transition probabilities, and the Förster– Dexter and Inokuti–Hirayama models of inter-ionic energy transfer are reviewed as the principal analytical tools underpinning this field. Reported single-ion, pairwise co-doped, and tri-doped rare-earth tellurite and related oxide-glass systems are compared in terms of their radiative parameters and CIE/CCT/CRI colorimetric outcomes. Although each of Eu3+, Tb3+, and Dy3+, and several pairwise combinations, have been extensively studied in tellurite hosts, the simultaneous tri-doping of a single tellurite glass with all three ions to realise a singlecomposition, single-excitation white emitter, a strategy already demonstrated in borate, phosphate, and halophosphate hosts, remains largely unexplored. This gap is identified as a clear and well-motivated direction for future research.