Materiales Orgánicos Conductores
Materiales Orgánicos Conductores
CNNCN
NC CN
S
S S
SN NNN
NNM
C
NCTCs
Metalomacrociclos
Materiales orgánicos
Metalomacrociclos
orgánicos conductores
Polímeros conjugadosFullerenos
Conducting Charge-Transfer ComplexesConducting Charge Transfer Complexes
S
S
S
STetrathiafulvene (TTF) 1973
CN
CN
NC
NC7,7,8,8-Tetracyanoquinodimethane (TCNQ)
1:1 Complex (crystallizes from acetonitrile)1:1 Complex (crystallizes from acetonitrile)
Displays metal-like conductivity over a wide temperature range(highest = 1.47 x 104 S/cm at 66 K; copper wire: = 6 x 105 S/cm at 298 K)
Complejos de transferencia de carga. TTF-TCNQ
CNNC
500 S 1 (TA)
NC CN
S
S S
S
= 500 Scm-1 (TA)
NC CN
“Orbitales Cristalinos”
Conductivity and Electronic StructureySolids: many bonded atoms, electronic states group into extended energy domains
BandsBand Structures:
Energy
nduc
tion
ban
“Crystalline Orbitals”
Energy gap: 0,5-1.5 eVEnergy gap > 3 eV
Fermi level
Empty levels
Con
du
Fermi level
Occupied levelsand
Occupied levels
alen
ce b
aM t l T C d ti it
Metal Semiconductor Insulator
Va Metal: T Conductivity
Semiconductor: T Conductivity
Conducting Charge-Transfer ComplexesConducting Charge Transfer Complexes
CNNC
e
CNNC
S S e S S
CNNC NC CN
SS SS
Mixed-valence salts (charge transfer is not complete)
It is basic!: Knowledge about the Red-ox potentials of donor and acceptor
Disposición eléctricamente conductorap
D+
D+ D+
A- A-
A-
D+
D D
A A-
A
D+
A-
D+
3,2-3,5 Å
DD+
D+ D+
AA- A-
A-
DD+
D D+
A A-
A-
D A-
D+
A- D
D+
D+
AA- A-
D+
D A A-
A D+
A-
D+A D+A- D+A D+A-
Aislante Semiconductor Conductor
DAD+A
Sales de valencia mixta
Disposición eléctricamente conductora
S
S
S
SMe
Me
Me
MeClO4
Electrocristalización
Moléculas dadoras de electronesMoléculas dadoras de electrones
S S SMe Me S S
S
S
S
S
TTF
Se
Se
Se
SeMe Me
MeMeTMTSF
S
S
S
S
S
S S
SBEDT-TTF (ET)TTF TMTSF BEDT-TTF (ET)
S SS S SO O Se SMe S
S SS
MDT-TTF
S SO OBEDO-TTF (BO)
Se SMe S
DMET
S
S
S
S S
S
Me
Me Se
Se
Se
Se S
SS
S
Se
Se
Se
Se S
SMe
Me
SMe
S,S-DMBEDT-TTF
SS
BEDT-TSF (BETS)
SMe
DMEDT-TSF
Moléculas aceptoras de electronesMoléculas aceptoras de electrones
NC CN
R1 R3 R1 R3
NCN
R2 R4
CNNCN
R2 R4
NC
TCNQ DCNQI
SSSS
S
S
SM
SS
S
S
S
SS
M(d it) n
C60
Buckminsterfullerene
M(dmit)2n
M = Ni, Pd, Pt
Efectos de la disminución de la TemperaturaEfectos de la disminución de la Temperatura
•Deformación de Peierls: Paso de Metal a semiconductor o aislante (deformación de la red)semiconductor o aislante (deformación de la red) al disminuir la T
•Superconductividad: Aumento drástico de la d i id d l di i i l T ( d ió d lconductividad al disminuir la T (reducción del
número de fonones o amplitud de las vibraciones d l d l i l f ó )de la red + acoplamiento electron-fonón)
Superconductores inorgánicos y orgánicos
Tl2Ba2Ca2Cu3O10
p g y g
100Tl2Ba2Ca2Cu3O10
RbTl C
K) NbN
ET Cu[N(CN) ]Cl
Rb3C60
RbTl2C60
10T (K
Hg
Nb
ET AuI-ET2Cu(NCS)2
-ET2Cu[N(CN)2]Cl
g
-ET2IBr2
-ET2AuI2
11900 1920 1940 1960 1980 2000
-ET2I3
1900 1920 1940 1960 1980 2000Año
Conducting Polymers: The BasicsConducting Polymers: The BasicsWhat is a polymer?A polymer is a chemical comprised of repeating molecules
with the same chemical structure.
What is conductance?Conductance is the ability of a material to carry electricalConductance is the ability of a material to carry electrical
charge.So what is a conducting polymer?So what is a conducting polymer?A conducting polymer joins these things to yield an organic
material able to take on properties normally seen only inmaterial able to take on properties normally seen only in metals.
Conducting PolymersConducting Polymers
P l ith l j t d h i i l t i d t ( 10 9 S/ )Polymers with polyconjugated chains: isolators or semiconductors ( = 10-9 S/cm)
Ti(IV)Polyacetylene (PA)
Ziegler-Natta-Shirikawa
H H( )
x n
cis-PA = 10-9 S/cm
trans-PA = 10-5 S/cm
AsF5
(halogens, FeCl3 , XeOF4 , ...)
“Doped” all-(E)-PA (s = 10-2 – 10-3 S/cm)
(metallic sheen; unstable: in air, conductivity drops within hours)
“Doping” ProcessDoping Process
R d ti b t d i t d j t d tRedox reaction between doping agent and conjugated system(i. e. polymer is oxidized to a polymeric cation, doping agent is the counterion)
Also, electrons hopping from chain to chain
Conducting Polymers
2 +
+n
3 I2n
+ 2 I3-
Molecular versus Band Models
M. Lögdlund et al.E
1
2 3
4 7
EE (eV)
56 8
El t
n
LUMO
Electronaffinity
BandgapHOMO
Ionizationpotential
Bandgap
potential
Electronic Structure
E Localized (l) level
Delocalized (d) level
- Key role in determining the optical propertiesKey role in determining the optical properties
Nobel Prize in Chemistry 2000
“For the Discovery and Development of Conductive Polymers”
Hid ki Shi kHideki ShirakawaUniversity of Tsukuba
Alan HeegerUniversity of California
t S t B b
Alan MacDiarmidUniversity of
P l iat Santa Barbara Pennsylvania
Conjugated Polymers
n Sn
Nnn
Trans-polyacetylene (t-PA)
n
Polythiophene (PT)
H
Polypyrrole (PPY)
n
Poly(p phenylene) (PPP)
n
Poly(p phenylenevinylene) (PPV)Poly(p-phenylene) (PPP) Poly(p-phenylenevinylene) (PPV)
NH NH N N
ny 1-y
Polyaniline (PAN)
Conducting Polymers
Relative low influence of the temperature
Electron-Phonon Coupling
EExcitation Doping
E
LES +1
E
Relaxationeffects
LES +1
Absorptioneffects
Emission IonizationRelaxationeffects
GS GS
Q Q
Chemical Doping of Conjugated Polymers
CB
Radical-cation / Polaron VB
+
Dication / Bipolaron
++++
Electronic Structure
SS
SS
SS
EE
LL L
POL2BIP2
BIP1
HH H
POL1
Polaron BipolaronNeutral
J. Cornil et al., Adv. Mater. 8, 447 (1996)
Optical Properties
SS
SS
SS
b. u
nits
)
Neutral
Bipolaron
tens
ity (a
rb
Polaron
Int
Energy (eV)600 800 1000 1200 1400 1600 1800 2000
Energy (nm)
J. Guay et al.Chem. Mater. 4, 1097 (1992) Electrochromic windows, sensors
Advantages
Combination of properties
M l Pl iMetals Plastics
Hi h d ti it Li htHigh conductivity LightnessEase of processing (spin coating)Low costLow costTailored synthesis
- Low oxidation potential (doping by I2, AsF5, SbF5, …)
Hi h l t ffi it (d i b Li N K )- High electron affinity (doping by Li, Na, K, …)
- Stability of the backbone not affected upon doping
Applications
- Batteries
El t t ti ti- Electrostatic coatings
S
Baytron P (Bayer) / Orgacon (AGFA)
S
O O
nn
SO3-
PEDOT PSS
- Electromagnetic shielding
- Electrochromic windows
- Actuators (Artificial muscles)
Ftalocianinas NFtalocianinas
NN
NN
N
N
NM
N
N
N
N
N
NMetallo- N
N
N FreeN
NN
N N
NM
Metallophthalocyanine
(PcM)N
NN
N
N
N
NH
H
Free Phthalocyanine
(PcH2)
N N
Q BandQ-Band
B or Soret-Band
Soret and Q bands
Ftalocianinas
MetallophthalocyaninesMetallophthalocyaninesMetallophthalocyaninesMetallophthalocyanines
NN
N
NNN
N
N
NM
N
UV-visible Spectra of Phthalocyanines and Analogues
1 P
NaphthalocyanineSubphthalocyanine
0 6
0.8
banc
e
Pc
0 2
0.4
0.6
Abs
orb
0
0.2
260 360 460 560 660 760260 360 460 560 660 760
Wavelength (nm)
Organization of Phthalocyanines in Condensed Phases
Si
N
NN N
N
OOO
O
OH
Liquid Crystals
OH
Si
OO
NN
NN
OO
LB FilmsN NN
C10H21H21C10
C10H21C10H21
LB-Films
NN
N
N
N M
C10H21C10H21
COOHHOOCLangmuir-Blodgett filmLangmuir film
Properties of Phthalocyanines. Applications
C d i P iSemiconducting materials
Conducting Properties Selective gas sensorsElectrochemical SensorsField Effect Transistors
Optical PropertiesPhotovoltaic Devices
Optical Properties Optical Recording DataPhotodynamic Therapy (PDT)
Nonlinear Optical Properties Frecuency DoublersOptical Limitersp
Conducting Metallo-Macrocyclesg y
N
N
NN
NNM
N
N
N
NM
N
N
N
NM
N
N
Phthalocyanine TetrabenzoporphyrinTetraphenylporphyriny yy y
Pc TPP TBP
Conducting Polymeric Metallo-Macrocyclesg y y
M M ML L L
PorphyrinPorphyrinor
Phthalocyanine
M M ML L L
M M ML L L
Conducting Polymeric Metallo-Macrocyclesg y y
NN
N
NN
N
N
N
N
N
NN
NM
N
N
NN
NMN N
CNCN CNN NN N N N CNCN CNN NN N N N
Aplications based on Conducting Properties ofAplications based on Conducting Properties of Phthalocyanines
Gas SensingArtificial Tongues and Noses
Gas Sensing
N NN
C10H21H21C10
C10H21C10H21
NN
N
N
N M
C10H21C10H21
Langmuir-Blodgett film COOHHOOC
Concept of electronic nose
“Inst ment fo med b an a a of chemical senso s ith“Instrument formed by an array of chemical sensors with cross-sensitivity coupled to a pattern recognition
software able to discriminate complex gases”.
First levelFirst level
Second levelSecond levelPCAPCAt /s
datos
resistenciaepitelioolfatori
corteza
bulboofatorio
cerebro
SoftwareSoftware
Thi d l lThi d l l
****
****
**
****
**
**Aceite CAceite C
Aceite BAceite B Aceite AAceite Anariz humana nariz electrónica
sensores
apolfatorio
Third levelThird levelNeural NetworkNeural Network
6
7
electrodos
material ibl
bulbofibras nerviosas
electrónica
moléculas de olor
sensibleneuronascilios
Electroactive sensing materialsElectroactive sensing materials
Development of a hybrid array of voltammetric sensors formed by electrodes chemically modified with materialsformed by electrodes chemically modified with materials
with rich electrochemical activity
Rare earth Bis-phthalocyanines Perylenes Conducting polymers
O O
N NRR R
O O
Ftalocianinas como Materiales Moleculares
N N
NN
N
N
NH
H NN
N
N
NM2- N
NN
N
N
N
N
N N
N
NN
N
N
Ftalocianinalibre (PcH2)
Forma aromática de la ftalocianina
Metaloftalocianina(MPc)
Propiedades físicas no convencionales (semiconductoras, ópticas...) Estabilidad térmica, química y ópticaVersatilidad de su estructura química modulación de sus propiedades
Síntesis de ftalocianinas
CuCN/DMFR
Br
Br
NH3
MeOH/MeONaR
CN
CNR N
NH
NH
TT
TCuCN/DMF ROH/DBNMX disolvente
NH2
R
N
R RR
N
R'
N
R'
NN
N
N
N
NM N
NHN
N
N
HN
NH3O+
MXN
NN
N
N
M
R
N
N
N
R RR
N
N
HNMX
R'
N
N
N
R'
Espectro UV-vis de las ftalocianinas
N
N
N N
N
N Banda QN
NN
N
N
N
NM N
NN
N
N
N
NH
HBanda Q
Banda B o Soret
Síntesis de ftalocianinas asimétricas
CN CN
R
R
+
CN
CN
R CNR
R HN
N
NH
N N
N
NH2
N
NH2
+
RR HN
NN
NH
N
NHR
NHR
R
Ensamblados moleculares dador-aceptor
Materiales para ONL
Dispositivos electrónicos Sistemas dador-aceptor
Sistemas fotosintéticos artificiales
p
Células solaresh
NN
D.+ A.-
Dador Puente AceptorN
N
N
N
M
e-
Ensamblados moleculares porfirina-C60
No covalente Covalente no conjugadoj g
Ph CH3
N
N
MeN
NN
NMPh
Ph
NHO
N
NN
NN
M Ph
Ph
Ph
Ph
N
PhPh
N
N
N
N
MN
CH3
PhS S
S S
R
n
Covalente conjugado
N
Ph
R
Covalente conjugado