Synthesis, Photo-Physical Properties, and Electroluminescence Characteristics of Iridium Phosphorescent Materials Based on Different β-Diketonate Ancillary Ligands
Abstract
1. Introduction
2. Results and Discussion
2.1. Synthesis and Thermal Properties
2.2. Crystalline Structures
2.3. Optical and Electrochemical Properties
2.4. Electrochemical Properties
2.5. Theorectical Calculations
2.6. EL Device Performance
3. Materials and Methods
3.1. General Information
3.2. Device Fabrication and Measurement
3.3. Compound Synthesis
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Complexes | Ir(dmppiq)2(dpacac) |
---|---|
Formula | C53H63IrN2O2 |
Formula weight | 952.25 |
Crystal system | monoclinic |
Space group | P121/c1 |
a [Å] | 15.9566(13) |
b [Å] | 14.4918(12) |
c [Å] | 40.128(3) |
α [°] | 90° |
β [°] | 90.850(2)° |
γ [°] | 90° |
V [Å3] | 9278.2(13) |
Z | 8 |
ρcalc [g cm−3] | 1.363 |
Reflections collected | 90,736 |
Independent reflections | 15,975 |
R, WR2(all) | 0.0943, 0.1711 |
R, WR2 [I > 2σ(I)] | 0.0599, 0.1546 |
GOF | 1.078 |
Compound | Ir(dmppiq)2(dpacac) | ||
---|---|---|---|
Ir(1)-O(1) | 2.128(5) | Ir(1)-O(2) | 2.130(5) |
Ir(1)-N(1) | 2.032(6) | Ir(1)-N(2) | 2.044(6) |
Ir(1)-C(16) | 2.007(7) | Ir(1)-C(36) | 2.006(8) |
O(1)-Ir(1)-O(2) | 88.6(2) | C(16)-Ir(1)-N(1) | 80.3(3) |
C(36)-Ir(1)-N(2) | 80.1(3) | N(1)-Ir(1)-N(2) | 174.1(2) |
C(16)-Ir(1)-O(1) | 174.5(3) | C(36)-Ir(1)-O(2) | 175.2(3) |
Compound | λabs a (nm) | λex a (nm) | λPL a (nm) | ФPL a | τ b (ns) | kr b (×106 s−1) | knr b (×106 s−1) | Td (°C) |
---|---|---|---|---|---|---|---|---|
Ir(dmippiq)2(acac) | 295(6.86), 348(3.56), 424(2.16), 479(1.32) | 281 | 620 | 0.74 | 111.32 | 6.65 | 2.34 | 399 |
Ir(dmippiq)2(macac) | 296(7.41), 349(3.67), 425(1.96), 477(1.21) | 285 | 620 | 0.75 | 117.48 | 6.38 | 2.13 | 357 |
Ir(dmipiq)2(dmacac) | 295(8.23), 347(3.96), 426(2.40), 478(1.35) | 273 | 621 | 0.68 | 144.97 | 4.69 | 2.21 | 364 |
Ir(dmippiq)2(tmacac) | 294(6.58), 348(3.14), 429(1.87), 480(1.04) | 281 | 623 | 0.72 | 209.05 | 3.44 | 1.34 | 355 |
Ir(dmippiq)2(ipacac) | 294(7.36), 348(3.05), 426(2.20), 478(1.25) | 277 | 619 | 0.70 | 157.04 | 4.46 | 1.91 | 377 |
Ir(dmippiq)2(deacac) | 294(7.23), 348(3.45), 428(2.16), 478(1.24) | 277 | 618 | 0.66 | 198.55 | 3.32 | 1.71 | 343 |
Ir(dmipiq)2(dmeacac) | 295(7.63), 348(3.79), 427(2.41), 478(1.44) | 287 | 619 | 0.72 | 164.53 | 4.38 | 1.70 | 333 |
Compound | Eox(Ir3+/Ir4+) (V) | Eg a (eV) | HOMO b (eV) | LUMO b (eV) |
---|---|---|---|---|
Ir(dmippiq)2(acac) | 0.55 | 1.99 | −4.95 | −2.96 |
Ir(dmippiq)2(macac) | 0.52 | 2.01 | −4.92 | −2.91 |
Ir(dmippiq)2(dmacac) | 0.51 | 1.98 | −4.91 | −2.93 |
Ir(dmippiq)2(tmacac) | 0.48 | 1.99 | −4.88 | −2.89 |
Ir(dmippiq)2(ipacac) | 0.55 | 1.99 | −4.95 | −2.96 |
Ir(dmippiq)2(deacac) | 0.52 | 1.99 | −4.92 | −2.93 |
Ir(dmippiq)2(dmeacac) | 0.51 | 1.98 | −4.91 | −2.93 |
HIC | Doping Concentration | Lmax a (cd/m2) | CEmax b (cd/A) | PEmax c (lm/W) | EQE d (%) | VD (V) @ 1, 100, 1000 cd/m2 | EL Peak e (nm) | CIE (x, y) |
---|---|---|---|---|---|---|---|---|
Ir(dmippiq)2(acac) | 12% | 4651 | 7.49 | 5.30 | 14.80 | 4.3, 7.7, 10.2 | 624 | (0.68, 0.32) |
Ir(dmippiq)2(macac) | 10% | 7026 | 7.55 | 3.95 | 13.42 | 5.9, 7.9, 9.6 | 624 | (0.68, 0.32) |
Ir(dmippiq)2(dmacac) | 10% | 8355 | 7.71 | 4.03 | 13.31 | 5.8, 7.8, 9.5 | 624 | (0.68, 0.32) |
Ir(dmippiq)2(tmacac) | 12% | 9973 | 10.89 | 8.77 | 13.45 | 2.7, 3.9, 5.7 | 625 | (0.68, 0.32) |
Ir(dmippiq)2(ipacac) | 10% | 9288 | 11.03 | 8.89 | 13.29 | 2.7, 3.8, 5.7 | 626 | (0.68, 0.32) |
Ir(dmippiq)2(deacac) | 10% | 5024 | 11.77 | 9.48 | 13.49 | 2.9, 5.3, 8.4 | 624 | (0.68, 0.32) |
Ir(dmippiq)2(dmeacac) | 16% | 13,960 | 15.63 | 12.60 | 18.26 | 2.6, 3.6, 5.4 | 625 | (0.68, 0.32) |
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Chang, Q.; Zhang, K.; Yan, C.; Xie, L.; Yi, Y.; Su, W.; Liu, W. Synthesis, Photo-Physical Properties, and Electroluminescence Characteristics of Iridium Phosphorescent Materials Based on Different β-Diketonate Ancillary Ligands. Molecules 2025, 30, 861. https://doi.org/10.3390/molecules30040861
Chang Q, Zhang K, Yan C, Xie L, Yi Y, Su W, Liu W. Synthesis, Photo-Physical Properties, and Electroluminescence Characteristics of Iridium Phosphorescent Materials Based on Different β-Diketonate Ancillary Ligands. Molecules. 2025; 30(4):861. https://doi.org/10.3390/molecules30040861
Chicago/Turabian StyleChang, Qiaowen, Ke Zhang, Caixian Yan, Liming Xie, Yuanqiuqiang Yi, Wenming Su, and Weiping Liu. 2025. "Synthesis, Photo-Physical Properties, and Electroluminescence Characteristics of Iridium Phosphorescent Materials Based on Different β-Diketonate Ancillary Ligands" Molecules 30, no. 4: 861. https://doi.org/10.3390/molecules30040861
APA StyleChang, Q., Zhang, K., Yan, C., Xie, L., Yi, Y., Su, W., & Liu, W. (2025). Synthesis, Photo-Physical Properties, and Electroluminescence Characteristics of Iridium Phosphorescent Materials Based on Different β-Diketonate Ancillary Ligands. Molecules, 30(4), 861. https://doi.org/10.3390/molecules30040861