A novel borosilicate glass based PiGs for WLEDs with tunable interface defects and high anti-thermal quenching power

A novel Eu3+ doped SiO2-B2O3-Al2O3-CaO-Na2O based borosilicate glass was designed to embed YAG: Ce for PiGs. It exhibits intense Eu3+ red emission with the average decay times of 6.8 μs and has the thermal conductivity of about 0.9 W/(mK) (five times that of silicone resin). The doped Eu3+ is over 10 mol% without any concentration quenching. The PiGs show variable decay time of Ce3+, which results from the tunable interface defects explained by the pseudo-solid solubility mechanism. The color of the WLEDs changes from cool white (6004 K) to warm white (3799 K) with more yellow emission added. The obtained maximal luminous efficiency and color rendering index are about 68 lm/W and 78, respectively. The anti-thermal quenching power of the PiGs is three times that of PiS based on the luminescent reduction. The PiG system can be used potentially for resin-free high power WLEDs. •A novel Eu3+ doped borosilicate glass was designed as the matrix for the YAG: Ce embedded phosphor-in-glasses (PiGs).•The glass system exhibits high refractive index of about 1.6 and high thermal conductivity of about 0.9 W·m−1·K−1 (five times that of silicone resin).•The concentration of Eu3+ ion can be up to 10 mol% without obvious concentration quenching of emission but still with the transparency over 70%.