Tunable white light by varying excitations in yttrium alumino bismuth borosilicate glasses co-doped with Dy3+-Eu3+ for cool WLED applications

Excitation‐dependent energy transfer and color tunability in Dy3+/Eu3+ co‐doped multi‐component borophosphate glasses

“…Furthermore, the Inokuti–Hirayama (I–H) model was used to evaluate the donor–acceptor interaction ( C Dy‐Eu ) and the average distance ( R o ) from the lifetime decay curve of the KZnBP:0.5Dy 3+ /1.0Eu 3+ glass (Figure 12), which is given by 1,52 $$$$\begin{equation}I(t) = {I}_o{\rm{exp}}\left[ - (t/{t}_o) - Q{(t/{t}_o)}^{(3/S)}\right],\end{equation}$$$$ $$$$\begin{equation}Q = 4\pi /3\left[\Gamma (1 - 3/S)\right]{N}_aR_o^3,\end{equation}$$$$ $$$$\begin{equation} {C}_{{\rm{Dy}} - {\rm{Eu}}} = {R_o^6}/{\tau}_{{\rm{Dy}}},\end{equation}$$$$where I ( t ) is related to the PL intensity time; t o denotes the emission lifetime for donors during absence of Eu 3+ . Euler's gamma function Γ (1 − 3/ S ) = 1.77 for S = 6 (d–d interaction), 1.43 for S = 8 (d–q interaction), and 1.3 for S = 10 (q–q interaction); N a is related to acceptor concentration; Q is related to the interaction parameter; C Dy‐Eu is the donor (Dy 3+ )–acceptor (Eu 3+ ) coupling constant; R o denotes the average distance between the donor (Dy 3+ ) and acceptor (Eu 3+ ) for ET to occur.…”

“…Therefore, the optimized KZnBP:0.5Dy 3+ /1.0Eu 3+ glass exhibits ET efficiency (η) of 61.58%. Furthermore, the Inokuti-Hirayama (I-H) model was used to evaluate the donor-acceptor interaction (C Dy-Eu ) and the average distance (R o ) from the lifetime decay curve of the KZnBP:0.5Dy 3+ /1.0Eu 3+ glass (Figure 12), which is given by 1,52 𝐼(𝑡) = 𝐼 𝑜 exp…”

“…Optical materials, such as glasses, glass ceramics, polymers, and phosphors, containing trivalent and/or divalent rare-earth (RE) ions have been extensively investigated over the last few decades owing to their potential applications. [1][2][3][4][5] RE ions, whose 4f intra-shell is shielded by states and combinations, such as single and dual combinations (co-dopants). Glasses containing various combinations of co-activated RE ions exhibit interesting optical properties, such as enhanced quantum efficiencies and lifetimes, generation of white light emission, enhanced lasing action, and ultra-broad telecommunication windows, because of their excellent energy-transfer (ET) dynamics.…”

“…Optical materials, such as glasses, glass ceramics, polymers, and phosphors, containing trivalent and/or divalent rare‐earth (RE) ions have been extensively investigated over the last few decades owing to their potential applications 1–5 . RE ions, whose 4f intra‐shell is shielded by 5s and 5p outer shells, possess exceptional optical, spectral, dielectric, and magnetic properties, which have given them significant importance in solid‐state lighting (SSL), high‐power lasers, photovoltaic cells, memory storage devices, optical fibers, and amplifiers in telecommunications 6–13 .…”

Trivalent rare-earth-codoped silicate phosphor materials (Ba1.3Ca0.7−x−y SiO4: xDy3+/yEu3+) for solid-state lighting

“…Hence, the singlematrix white light-emitting phosphors were considered as a solution for realizing high efficiency LED devices. Here, the single matrix phosphor is known to have many advantages such as high color rendering index, low color temperature, and high luminous efficiency [14]. Importantly, this approach usually requires a near-UV LED chip instead of a blue InGaN device, indicating the intended device has a different configuration compared to the commercialized white LED developed by the Nichia Corporation in 1996 [15,16].…”