Damage Threshold Data
(Summary)
Optical Damage Thresholds for Various Samples
Sample
Fluence DT (J/cm2)
DNA/CTMA on SLG Substrate
2.3 to 2.6
DNA/CTMA W/O Substrate
2.1 (sample curved)
Fused Silica
2.7 to 4.5 (AFRL = 4.3)
SiC Semi-conducting
0.6
SiC Conducting
0.65
PMMA 380
0.5
PMMA 455
0.6
Optical Damage Threshold Comparable to that of Fused Silica
Thermal Conductivity
• Large Thermal Conductivity
• 0.12 W/mK for PMMA[1]
• 0.82 W/mK DNA (~7X > PMMA)
• 0.62 W/mK DNA-CTMA (~5X > PMMA)
[2]
DNA & DNA/CTMA
[measured - AFRL]
PMMA [1]
Potential For
Getting Heat Out
[1] Takashi Kodama, et al., “Heat Conduction through a DNA-Gold Composite,” Nano Letters, 9, 2005 (2009)
[2] Hartnett, Cho, Greene and Bar-Cohen, Advances In Heat Transfer, Volume 39, p. 174, Academic Press, 2006
DNA Biopolymer-Based
White Solid State Lighting
Materials
• Ce3+:YAG Phosphor:
Merck: Isiphor YGA 588100 (LED phosphor)
• Epoxy:
Epoxy Technology: EPO-TEK OG142-112 (LED epoxy)
• DNA-Biopolymer:
12 wt% DNA-CTMA-C4H9OH
(500 KDa, soxhlet rinse - no dialysis)
• DNA – Ogata Research Laboratory
• CTMA – Sigma Aldrich (25 wt% CTMA in solution)
• C4H9OH – Sigma Aldrich
DNA Biopolymer-Based
White Solid State Lighting
Processing
33 wt% Ce3+:YAG-Epoxy
• 45 µl drop onto nylon cap
• UV cure 100 mW for 10 min
• bake @ 40oC for 60 min
33 wt% Ce3+:YAG-DNA/CTMA
• 45 µl drop onto nylon cap
• bake @ 40oC for 60 min
(no UV curing required)
DNA Biopolymer-Based
White Solid State Lighting
Characterization
Phosphor + Host
Light Source: Photon Micro Light (λ = 470 nm)
Sony 100 Camera
Speed: 1/160 second
Aperture: F5.6
33 wt% Ce3+:YAG-Epoxy
33 wt% Ce3+:YAG-DNA/CTMA
DNA Biopolymer-Based
White Solid State Lighting
33 wt% Ce3+:YAG-Epoxy
33 wt% Ce3+:YAG-DNA/CTMA
Central Bright Region 6X Larger for DNA-Based Material
(6X Brighter ?)
Sony 100 Camera
Speed: 1/160 second
Aperture: F5.6
IGOR PRO
Photon Micro Light
(λ = 470 nm)
33 wt% Ce3+:YAG-DNA/CTMA
33 wt% Ce3+:YAG-Epoxy
iPhotoLux app for Apple iPod Touch
J. Grote, “Light emitting diode with a deoxyribonucleic acid (DNA) biopolymer”, US Patent 8,093,802 B1, Jan. 10, 2012
DNA Biopolymer-Based
White Solid State Lighting
Blue LED
33 wt% Ce3+:YAG-Epoxy
33 wt% Ce3+:YAG-DNA/CTMA
More Blue Component
with Epoxy-Based Host
More Longer Wavelength Components
with DNA-Based Host
DNA Biopolymer-Based
White Solid State Lighting
Chromaticity (CIE 1931 [x, y] Gamut Chart)
33 wt% Ce3+:YAG-DNA/CTMA
[0.2441, 0.2877]
Exact White
[0.3127, 0.3290]
33 wt% Ce3+:YAG-Epoxy
[0.1975, 0.2177]
DNA Biopolymer-Based
White Solid State Lighting
Heat Exposure
Epoxy
DNA-CTMA
90
90
80
70
60
Before 24hr @ 90C
50
After 24hr @ 90C
40
% Trnasmittance
100
% Transmittance
100
80
70
60
Before 24hr @ 90C
50
After 24hr @ 90C
40
2nd 24hr @90C
30
2nd 24hr @90C
30
20
20
340
440
540
640
Wavelength (nm)
740
340
440
540
Wavelength (nm)
Epoxy - 66.11 µm thick (flow coat)
DNA/CTMA - 59.33 µm thick (flow coat)
640
740
DNA Biopolymer-Based
White Solid State Lighting
24 Hour UV Exposure
(λ = 365 nm)
DNA-CTMA
100
100
90
90
% Transmittance
% Transmittance
Epoxy
80
70
60
50
2nd 24hr @90C
40
Final 1hr UV Cure
80
70
60
50
2nd 24hr @ 90C
40
Final 1hr UV Cure
30
30
20
20
340
440
540
640
Wavelength (nm)
740
340
440
540
640
Wavelength (nm)
Epoxy - 66.11 µm thick (flow coat)
DNA/CTMA - 59.33 µm thick (flow coat)
740
DNA Biopolymer-Based
White Solid State Lighting
Cost Analysis
Cost Per Gram of Material
• DNA/CTMA
• 0.5g DNA + 4 ml CTMA
$6.75
(25 wt% solution of CTMA in H2O)
• 12 wt% DNA/CTMA in C4H9OH
• EPO-TEK OG142-112 Epoxy
$0.86 (~4X more)
$0.20
Future DNA materials (estimated 10X-100X cost reduction)
• 12 wt% DNA/CTMA in C4H9OH
$0.16 (~1.25X less)
$0.06 (~3X less)
Phosphor Coating Accounts for 5% - 10% of Cost of White LED
Deposition Techniques
That Can Be Used
Spin Deposit
Cast
Vacuum Deposit
Electro-Spin
Flow Coat
Spray Deposit
Ink Jet Print
Pulsed Laser
Enhanced Fluorescence in Electrospun
Dye-Doped DNA Nanofibers
DNA-CTMA-Hemi22
Nanofiber
PhosphorDNA/CTMA
~10X
Film
Fluorescent Dye Hemi22
λex = 460 nm
(Hemi22) 4-[4-dimethylaminostyryl]1-docosylpyridinium bromide
Acceptor Dye
Increased Surface Area
Normalized Fluorescence
Sample
Intensity
PMMA Film
2.2 x106
PMMA Nanofiber
1.1 x 107
DNA–CTMA Film
3.9 x 107
DNA–CTMA Nanofiber
2.3 x 108
Y. Ner, et. al., “Enhanced Fluorescence in Electrospun Dye-Doped DNA Nanofibers ", Soft Matter, 4, 1-7, (2008)
Summary & Conclusions
(DNA-CTMA Host vs Epoxy)
+ Brighter (Higher Efficiency ?)
+ Closer to Exact White Light (More Longer Wavelengths Present)
+ Higher UV & Comparable Heat Tolerance (Longer Lifetime ?)
+ Lower Optical Loss
+ Acceptable Temperature Stability
+ Higher Thermal Conductivity
+ Higher Optical Damage Threshold
+ Higher Photochemical Stability
+ Comparable Low Temperature Processing
+ No UV Curing Required
+ Longer Shelf Life
+ Environmentally Friendly
− ~4X More Expensive (Currently)
+ Potentially ~1.25X-3X Less Expensive (Future)
Cost may not be an issue
Acknowledgments
 Edison Materials Technology Center (EMTEC)
 Air Force Research Laboratory
Materials &Manufacturing Directorate (AFRL/RX)
 Merck (Ce3+:YAG phosphor)
 Rajesh Naik (jpeg to gamut chart conversion)
 Timothy Gorman (IGOR PRO conversion)
 Danny Grote (iPhotoLux conversion)
 Elizabeth Steenbergen (spectral data)
 ID Cast
 Wright Brothers Institute