Healthy and High‐Quality Single‐Source Lighting Based on Double‐Doped Tin Halide Engineering

Abstract Single‐source white light‐emitting diodes (WLEDs) with smart regulation of correlated color temperature (CCT) are indispensable for the next generation of WLEDs aimed at healthy and high‐quality illumination, where a suitable CCT value is closely related to our emotions and circadian rhythm. Herein, this work constructs a single‐component emission layer WLED with high performance for controllable daily lighting through Bi 3+ /Te 4+ dual‐doped Cs 2 SnCl 6 engineering. The efficient energy transfers between triple self‐trapped exciton states from Bi 3+ /Te 4+ doping allow two tunable broadband emissions that can cover the full‐color region, thereby yielding a standout color‐rendering index of 94 for the fabricated WLED. The robust stability against heat, ultraviolet light, and environmental oxygen/water induces a long half‐lifetime of WLED up to 1104 h. Moreover, the dual‐doped strategy endows the emitter with excitation‐dependent luminescent characteristics, enabling the single emissive layer device to realize switching control of cold‐, positive‐, and warm‐white light by converting the excitation chip. Meanwhile, continuous regulation of CCT for different application scenarios can be achieved by adjusting the current of different chips. This work constitutes a solid step toward building single‐source WLEDs for smart and healthy lighting based on dual‐doped lead‐free metal halides.