Broadband White‐Light‐Emitting Electrochemical Cells

Abstract

Emerging organic light‐emitting devices, such as light‐emitting electrochemical cells (LECs), offer a multitude of advantages but currently suffer from that most efficient phosphorescent emitters are based on expensive and rare metals. Herein, it is demonstrated that a rare metal‐free salt, bis(benzyltriphenylphosphonium)tetrabromidomanganate(II) ([Ph3PBn]2[MnBr4]), can function as the phosphorescent emitter in an LEC, and that a careful device design results in the fact that such a rare metal‐free phosphorescent LEC delivers broadband white emission with a high color rendering index (CRI) of 89. It is further shown that broadband emission is effectuated by an electric‐field‐driven structural transformation of the original green‐light emitter structure into a red‐emitting structure.

Enhanced stability and complex phase behaviour of organic–inorganic green-emitting ionic manganese halides

“…Yet some shift of the half-wave potential can be seen in the CV for 2 compared to 1 and 3 . We have observed for other tetrabromido( ii ) complexes that a structural change and, possibly, aggregation can occur under applied fields, 80 which could be an explanation for the observation.…”

“…We have observed for other tetrabromido(II) complexes that a structural change and, possibly, aggregation can occur under applied fields. 80 This could be an explanation for the observation made.…”

Manganese (II) Halides for X‐Ray Imaging and Moisture Detection

“…[ 42 ] The optical bandgap is 1240/λ Start , and λ Start is the starting point of the low energy absorption band. [ 43,44 ] The optical bandgap of EDBEMnBr 4 (Table S4, Supporting Information) is estimated to be ≈2.66 eV. The temperature‐dependent PL spectra of EDBEMnBr 4 , are shown in Figure 2c and Figure S6 (Supporting Information).…”

Photophysical Tuning of Imidazolium Tetrahalidomanganate(II) Complexes towards Highly Efficient Green Emitters with Near‐Unity Quantum Yield

“…[27][28][29][30][31][32] Notably, tetrahalidomanganate(II) complexes are highly promising materials to be applied as emitters in optoelectronic devices, as they are easy to synthesize and suitable for energyefficient solution processing. [29,32,33] However, up until now, the application of tetrahalidomanganates as light emitters is still limited, and external quantum efficiencies of the few reported systems are low, compared to the commercially used devices, [27,29,34,35] prompting the need for further research and development. To achieve higher efficiency of light emitters based on organic-inorganic tetrahalidomanganates, compounds with larger photoluminescence quantum yield (Φ) values should be designed.…”