Os(ii) metal phosphors bearing tridentate 2,6-di(pyrazol-3-yl)pyridine chelate: synthetic design, characterization and application in OLED fabrication

Metal Complexes with Azolate‐Functionalized Multidentate Ligands: Tactical Designs and Optoelectronic Applications

“…[40] Os II complex 34 is non-emissive in both fluid and solid states at room temperature, which is attributed to the fast non-radiative deactivation inducedb yt he higherf requency vibrationc oupled with water.H owever,h ighere mission QY was achievedb yi ncorporation of PPh 2 Me or bpy,w hich afforded monocarbonyl complexes [Os(dpz CF3 py)(PPh 2 Me) 2 (CO)] (35)a nd [Os(dpz CF3 py)(CO)(bpy)] (36), respectively.I ti sn otable that in complex 35 there is the phosphine ligandsa re in a trans arrangement, while complex 36 exhibited ad istinctive cis arrangemento ft he nitrogen donor atoms from bpy.T he marked difference lies in the good p-accepting capability of the phosphine (versus the respective nitrogen donor) and thus weakening the bondingo ft he trans carbonyl ligand for further phosphine coordinationd uring reaction, while bpy favors the replacemento ft he cis carbonyl ligand due to the inherentg eometricalconstraint. X-ray analysis showedt he presence of al igated water that enteredt he reactiond uring workup.…”

Perspective on carbazole-based organic compounds as emitters and hosts in TADF applications

“…These PHOLED devices achieved close to 100% internal quantum efficiency due to singlet-triplet mixing through effective spinorbit coupling. 7,8 However, transition metal complexes 9 based on metals such as iridium, 10 platinum, [11][12][13] osmium, 14 europium, 15 and ruthenium 16 are costly and scarce resources of low abundance, and are as such not sustainable for mass consumer goods applications. In addition, upon disposal, these materials are potentially harmful for the environment.…”

Facile Generation of Thermally Activated Delayed Fluorescence and Fabrication of Highly Efficient Non‐Doped OLEDs Based on Triazine Derivatives

“…These EL spectraw ith pure emissionsi ndicate that the exciton formationz onei sl ocated within the EML and the generated exciton is well-confined in the EML. [39] Figure 8(b) depictst he current density-voltage (J-V)c haracteristics.A si ndicated, since device A1 was constructed by using materials with lower energy band gaps, yellow-green emitting device A1 reasonably presents am uch higherc urrent density than those of sky-blue-emitting device B1 and trueblue-emitting C1. On the other hand, compared with the current density of both blue devices under lower operating vol-tages (cf.…”