Efficient White Polymer Light‐Emitting Diode (WPLED) Based on Single‐Component Eu³⁺–Tb³⁺‐Containing Metallopolymer

Abstract Despite the excellent physical properties of single‐component Eu³⁺–Tb³⁺‐containing metallopolymers, the development of their flexible white polymer light‐emitting diodes (WPLEDs) for portable full‐color flat displays remains a formidable challenge. Herein, the WPLEDs from a metallopolymer Poly(NVK‐co‐2‐co‐7) are reported, in which [Eu(DBM)₃(4‐vp‐PBI)] (2) and [Tb(tba‐PMP)₃(4‐vp‐PBI)] (7) with different localized circumstances are grafted into poly(N‐vinyl‐carbarzole) (PVK). In this design, both Dexter and Förster energy transfers occur, which endow a photoluminescent quantum yield up to 22.3% of the straightforward high‐quality white‐lights. Contributing from the stepwise alignment of frontier molecular orbitals of Poly(NVK‐co‐2‐co‐7) as the emitting layer in combination with CBP‐ and BCP‐assisted carrier‐transports, a reliable WPLED with the record‐renewed electroluminescent performance (L^Max = 388.0 cd m⁻², η_c^Max = 31.1 cd A⁻¹, η_p^Max = 15.0 lm W⁻¹, η_EQE^Max = 18.1%, and weak efficiency‐roll‐off) among previous organo‐Ln³⁺‐based white organic light‐emitting diodes/WPLEDs is achieved. This finding renders a single‐component Eu³⁺–Tb³⁺‐containing metallopolymers a potential new platform to cost‐effective flexible WPLEDs for practical applications.