Synergistic effect of energy transfer offset enabling anti-thermal quenching

• The luminous color regulation is achieved by the Tm 3+ →Dy 3+ ET. • Suppressed Concentration Quenching Brightens Dy 3+ Emitters. • The anti-TQ originates from the SE of the Tm 3+ →Dy 3+ ET and high structural rigidity . • The prepared WLED device has a high Ra = 83.9 and a low CCT = 3345 K. Thermal quenching and brightness are significant challenges for many phosphors, particularly those used in WLEDs, restricting their effectiveness for large-scale implementation. However, developing phosphors with both anti-thermal quenching (anti-TQ) and high brightness remains quite challenging. Here, we report on the synergistic effect (SE) of energy transfer (ET) offset enabling anti-TQ and intrinsic suppression of concentration quenching (CQ) in sensitized photoluminescent schemes. Anti-TQ (102.1%@400 K) is achieved through the synergistic effect of ET and strong structural rigidity . The chromaticity-shifting (ΔEs) level is 8.63×10 −3 , indicating that it retains PL thermal stability comparable to commercial phosphors. The sensitization effects were investigated both experimentally and through theoretical models as a function of Dy 3+ concentrations. The ET process were studied based on the force electric dipole at each ion, achieving an efficiency of 83.4% and ET rates of 165.8%. The Ca 3 ScAl 3 B 4 O 15 :0.015Tm 3+ ,0.12Dy 3+ -based WLED exhibits satisfactory parameters of R a (83.9) and low-CCT (3345 K). The results highlight how emitters play a crucial role in dissipating excitation energies, offering a new avenue for improving the efficiency of sensitized luminescent materials. An intrinsic suppression of concentration quenching in sensitized luminescent systems, by exploiting the competitive relationship between light emitters and quenchers in excitation energies from sensitizers, is stated. We turned to study the sensitized PL properties of Dy 3+ with high concentrations of Tm 3+ that have been totally ignored to date. Anti-TQ is achieved via the synergistic effect of ET and high structural rigidity . WLED devices were fabricated exhibiting low CCT (3345) and high Ra (83.9).