Figure 19.1. Molecular structures of several conjugated polymers. (From Ref. 1 by permission of American Physical Society.)

Figure 19.2. Device structure of an organic light-emitting diode.

Glass

ITO

HTL

Alq3

Metal Cathode

Figure 19.3. Layer-by-layer chemisorptive self-assembly of siloxane dielectric layers on an ITO anode. (From Ref. 8 by permission of American Chemical Society.)

Figure 19.4. a) External quantum efficiency and b) luminous efficiency as a function of the number of self-assembled siloxane layers. (From Ref. 8 by permission of American Chemical Society.)

Figure 19.5. Schematic energy level diagram of an ITO/PPV/Al LED indicating the electron affinity (EA), ionization potential (IP), workfunction (), and injection barriers E. (From Ref. 10 by permission of Macmillan Magazines Ltd.)

Figure 19.6. Schematic of the electronic density of states across a graded interlayer fabricated using electrostatic layer-by-layer assembly. (From Ref. 13 by permission of Macmillan Magazines Ltd.)

Figure 19.7. Typical current-voltage characteristics of a solar cell under illumination. The identified quantities are discussed in the text.

VMP

IMP

VOC

ISC

V

I

Figure 19.8. Schematic illustration of photoinduced charge transfer in blends of MEH-PPV and C60 derivatives. Also

illustrated are the phase separation into a bicontinuous network and the general configuration of polymer photovoltaic device. (From Ref. 17 by permission of American Association for the Advancement of Science.)

Figure 19.9. I-V characteristics of a (A) Ca/MEH-PPV:[6,6]PCBM/ITO device and (B) Ca/MEH-PPV/ITO device in the dark (open circles) and under 20 mW/cm2 illumination at 430 nm (solid circles). (From Ref. 17 by permission of American Association for the Advancement of Science.)

Figure 19.10. Photoluminescence of an unheated MEH-PPV/C60 bilayer

device (solid) and two heated MEH-PPV/C60 devices (5 minutes at 150o C

(dotted) and 5 minutes at 250o C (dashed)). (From Ref. 21 by permission of American Institute of Physics.)

500 600 700 8000

1000

2000

3000

4000

Pho

tolu

min

esce

nce

[a.u

.]

Wavelength [nm]

Figure 19.11. Photoresponsivity of a MEH-PPV device (squares, magnified by 5x), an unheated MEH-PPV/C60 bilayer device (circles), a MEH-PPV/C60

bilayer device that was heated at 150 oC for 5 minutes (triangles) and a MEH-PPV/C60 bilayer device that was heated at 250 oC for 5 minutes

(diamonds). (From Ref. 21 by permission of American Institute of Physics.)

300 400 500 600 700

0

5

10

15

20

x5

Pho

tore

spon

sivi

ty [m

A/W

]

Wavelength [nm]

Figure 19.12. TEM images of 20 wt % (A) 7 nm by 7 nm and (B) 7 nm by 60 nm CdSe nanocrystals in P3HT and cross-section TEMs of (C) a 110 nm thick film of 60 wt% 10 nm by 10 nm nanocrystals and (d) a 100 nm thick film of 40 wt % 7 nm by 60 nm nanorods in P3HT. (From Ref. 23 by permission of American Association for the Advancement of Science.)

Figure 19.13. Mach-Zehnder waveguide modulator. Through (2), the electrical input modulates the optical output.

Figure 19.14. Schematic illustration of polar, self-assembled multilayers grown with Zr phosphate-phosphonate interlayers. (From Ref. 28 by permission of American Association for the Advancement of Science.)

Figure 19.15. Schematic cross-section of an electro-optic modulator waveguide with an active organic self-assembled superlattice (SAS). (From Ref. 32 by permission of American Institute of Physics.)

Figure 19.16. Schematic illustration of polar order in a film fabricated by the layer-by-layer electrostatic deposition process. The NLO chromophores are represented by the arrows.

- - - - - - - - -

++

++ + + +

+ + +

Glass Substrate

++

++ + + +

+ + +

- - - - - - - - -

++

++ + + +

+ + +

Glass Substrate

++

++ + + +

+ + +

Figure 19.17. Absorbance at 500 nm and square root of the SHG intensity as a function of the number of bilayers for films made by layer-by-layer polyelectrolyte deposition. (From Ref. 38 by permission of American Institute of Physics.)

Figure 19.18. Schematic illustration of a hybrid covalent/electrostaic deposition process for fabricating polar self-assembled multilayers. (From Ref. 40 by permission of WILEY-VCH Verlag GmbH & Co.)

*

NH2 NH2 NH2 NH2 NH2

n

Substrate

NaO3S SO3Na

N N

OHNH

N

N

N

ClCl

*

NH NH2 NH2 NH2 NH2

n

NaO3S SO3Na

N N

OHNH

N

N

N

Cl

+ +

Substrate

+ HCl

- -

+ - +-