Highly Efficient Candlelight Organic Light-Emitting Diode with a Very Low Color Temperature
Abstract
:1. Introduction
2. Result and Discussion
2.1. Synthesis
2.2. Theoretical Analysis
2.3. Thermal Characteristics
2.4. Photophysical and Electrochemical Characteristics
2.5. Charge Transporting Properties (HOD/EOD)
2.6. Electroluminescent Properties
2.7. Comparison between the Studied Very Low Color-Temperature Candlelight Organic LED and Commercial Luminaires
3. Materials and Methods
3.1. Synthesis
3.2. Characterization and Measurements
3.3. Materials
3.4. Device Fabrication and Characterization
3.5. Theoretical Calculation of MSS and MPE
3.5.1. Maximum Permissible Exposure-Limit (MPE)
3.5.2. Melatonin Suppression Sensitivity
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Conflicts of Interest
Sample Availability
References
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Material | λem a (nm) | Tm b (°C) | Tg c (°C) | Td d (°C) | HOMO e (eV) | LUMO e (eV) | HOMO f (eV) | LUMO f (eV) | Et g (eV) | Es g (eV) | Et h (eV) | Es h (eV) | Band Gap i (eV) | Refs. |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
BPMO | 393 | 199 | 63 | 340 | 5.12 | 0.71 | 5.39 | 1.54 | 3.02 | 3.70 | 2.87 | 3.44 | 3.85 | [37] |
CBP | 369 | 62 | 320 | - | - | 6.0 | 2.9 | 2.56 | 3.49 | 2.6 | - | 3.1 | [38,39,40] |
Hosts. | Emitter (wt%) | DV (V) | OV (V) | PE (lm/W) | CE (cd/A) | EQE (%) | CT (K) | CIE | Lmax (cd/m2) | |
---|---|---|---|---|---|---|---|---|---|---|
PO-01 | Ir(2-phq)3 | @100/1000/10,000/max. (cd/m2) | ||||||||
BPMO | 10 | 10 | 2.8 | 3.2/4.1/6.4/2.9 | 22.0/16.9/5.6/23.7 | 22.4/21.6/11.6/ 22.4 | 10.2/9.6/5.3/ 10.2 | 1690/1707/1786 | (0.58, 0.42)/(0.58, 0.42)/(0.57, 0.43) | 14,950 |
CBP | 10 | 10 | 3.2 | 4.1/5.7/-/3.5 | 7.4/3.9/-/9.6 | 10.3/7.4/-/11.7 | 4.7/3.2/-/6.8 | 1768/1782/- | (0.57, 0.42)/(0.57, 0.42)/- | 8393 |
ETL (nm) | DV (V) | OV (V) | PE (lm/W) | CE (cd/A) | EQE (%) | CT (K) | CIE | Lmax (cd/m2) |
---|---|---|---|---|---|---|---|---|
@100/1000/10,000/max. (cd/m2) | ||||||||
45 | 2.8 | 3.2/4.1/6.4/ 2.9 | 22.0/16.9/5.6/23.1 | 22.4/21.6/11.6/22.1 | 10.2/9.6/5.3/9.5 | 1690/1707/1786/- | (0.58, 0.42)/(0.58, 0.42)/(0.57, 0.43) | 14,950 |
50 | 2.8 | 3.2/4.1/6.6 | 24.7/17.9/5.4/24.8 | 24.8/23.3/11.3/28.8 | 10.6/9.9/-/10.6 | 1785/1795/1898/- | (0.57, 0.43)/(0.57, 0.43)/- | 13,520 |
55 | 2.9 | 3.3/4.6/7.1 | 22.9/10.4/4.9/23.7 | 24.2/15.3/11/24.2 | 10.7/6.7/-/10.7 | 1732/1744/1837/- | (0.57, 0.43)/(0.57, 0.43)/- | 13,250 |
Light Source | Spectrum | CT (K) | MSS (%) | MPE (s) @100 lx |
---|---|---|---|---|
This work | 1690 | 1.33 | 57,696 | |
Candle Light | 1884 | 4.0 | 2750 | |
Incandescent Bulb | 2444 | 11.5 | 1100 | |
Warm-white LED | 2704 | 8.0 | 1000 | |
Warm-white organic LED | 3080 | 6.9 | 1050 | |
Cold-white organic LED | 4034 | 12.8 | 590 | |
Cold-white LED | 5549 | 19.8 | 380 | |
Cold-white CFL | 5843 | 29.9 | 320 |
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Shahnawaz; Siddiqui, I.; Nagar, M.R.; Choudhury, A.; Lin, J.-T.; Blazevicius, D.; Krucaite, G.; Grigalevicius, S.; Jou, J.-H. Highly Efficient Candlelight Organic Light-Emitting Diode with a Very Low Color Temperature. Molecules 2021, 26, 7558. https://doi.org/10.3390/molecules26247558
Shahnawaz, Siddiqui I, Nagar MR, Choudhury A, Lin J-T, Blazevicius D, Krucaite G, Grigalevicius S, Jou J-H. Highly Efficient Candlelight Organic Light-Emitting Diode with a Very Low Color Temperature. Molecules. 2021; 26(24):7558. https://doi.org/10.3390/molecules26247558
Chicago/Turabian StyleShahnawaz, Iram Siddiqui, Mangey Ram Nagar, Abhijeet Choudhury, Jin-Tin Lin, Dovydas Blazevicius, Gintare Krucaite, Saulius Grigalevicius, and Jwo-Huei Jou. 2021. "Highly Efficient Candlelight Organic Light-Emitting Diode with a Very Low Color Temperature" Molecules 26, no. 24: 7558. https://doi.org/10.3390/molecules26247558