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