BACKGROUND & AIMS:
:Core/shell (C/S)-structured upconversion nanophosphor (UCNP)-incorporated polymer waveguide-based flexible transparent displays are demonstrated. Bright green- and blue-emitting Li(Gd,Y)F4:Yb,Er and Li(Gd,Y)F4:Yb,Tm UCNPs are synthesized via solution chemical route. Their upconversion luminescence (UCL) intensities are enhanced by the formation of C/S structure with LiYF4 shell. The Li(Gd,Y)F4:Yb,Er/LiYF4 and Li(Gd,Y)F4:Yb,Tm/LiYF4 C/S UCNPs exhibit 3.3 and 2.0 times higher UCL intensities than core counterparts, respectively. In addition, NaGdF4:Yb,Tm/NaGdF4:Eu C/S UCNPs are synthesized and they show red emission via energy transfer and migration of Yb3+ → Tm3+ → Gd3+ → Eu3+. The C/S UCNPs are incorporated into bisphenol A ethoxylate diacrylate which is used as a core material of polymer waveguides. The fabricated stripe-type polymer waveguides are highly flexible and transparent (transmittance > 90% in spectral range of 443-900 nm). The polymer waveguides exhibit bright blue, green, and red luminescence, depending on the incorporated UCNPs into the polymer core, under coupling with a near infrared (NIR) laser. Moreover, patterned polymer waveguide-based display devices are fabricated by reactive ion etching process and they realize bright blue-, green-, and red-colored characters under coupling with an NIR laser.
背景与目标:
: 展示了芯/壳 (C/S) 结构的上转换纳米磷酸盐 (UCNP) 结合的基于聚合物波导的柔性透明显示器。通过溶液化学路线合成了亮绿色和蓝色的Li(Gd,Y)F4:Yb,Er和Li(Gd,Y)F4:Yb,Tm UCNPs。通过与LiYF4壳层形成C/S结构,它们的上转换发光 (UCL) 强度得到增强。Li(Gd,Y)F4:Yb、Er/LiYF4和Li(Gd,Y)F4:Yb、Tm/LiYF4 C/S UCNPs分别表现出比核心对应物高3.3和2.0倍的UCL强度。此外,合成了NaGdF4:Yb,Tm/NaGdF4:Eu C/S ucnp,它们通过能量转移和Yb3 + → Tm3 + → Gd3 + →→ Eu3 + 的迁移显示红色发射。将C/S ucnp掺入双酚a乙氧基二丙烯酸酯中,该双酚a乙氧基二丙烯酸酯用作聚合物波导的核心材料。所制造的条纹型聚合物波导是高度柔性和透明的 (在443-900 nm的光谱范围内透射 > 90%)。聚合物波导在与近红外 (NIR) 激光器耦合的情况下,显示出明亮的蓝色,绿色和红色发光,具体取决于掺入聚合物核中的ucnp。此外,图案化的基于聚合物波导的显示设备是通过反应离子蚀刻工艺制造的,它们在与NIR激光器耦合的情况下实现了明亮的蓝色,绿色和红色特征。