Compact ultrabroadband light-emitting diodes based on lanthanide-doped lead-free double perovskites
Shilin Jin, Renfu Li, Hai Huang, Naizhong Jiang, Jidong Lin, Shaoxiong Wang, Yuanhui Zheng, Xueyuan Chen, Daqin Chen
Abstract
Abstract Impurity doping is an effective approach to tuning the optoelectronic performance of host materials by imparting extrinsic electronic channels. Herein, a family of lanthanide (Ln 3+ ) ions was successfully incorporated into a Bi:Cs 2 AgInCl 6 lead-free double-perovskite (DP) semiconductor, expanding the spectral range from visible (Vis) to near-infrared (NIR) and improving the photoluminescence quantum yield (PLQY). After multidoping with Nd, Yb, Er and Tm, Bi/Ln:Cs 2 AgInCl 6 yielded an ultrabroadband continuous emission spectrum with a full width at half-maximum of ~365 nm originating from intrinsic self-trapped exciton recombination and abundant 4f–4f transitions of the Ln 3+ dopants. Steady-state and transient-state spectra were used to ascertain the energy transfer and emissive processes. To avoid adverse energy interactions between the various Ln 3+ ions in a single DP host, a heterogeneous architecture was designed to spatially confine different Ln 3+ dopants via a “DP-in-glass composite” (DiG) structure. This bottom-up strategy endowed the prepared Ln 3+ -doped DIG with a high PLQY of 40% (nearly three times as high as that of the multidoped DP) and superior long-term stability. Finally, a compact Vis–NIR ultrabroadband (400~2000 nm) light source was easily fabricated by coupling the DiG with a commercial UV LED chip, and this light source has promising applications in nondestructive spectroscopic analyses and multifunctional lighting.