Push-pull types of conjugated polymers (PTTICN, PTTICNR and PTTIFR) containing TTI as electron pushing unit and 2-pyriminecarbonitrile or 2-fluoropyrimidine as electron pulling unit were synthesized.
In the doping process, electron emitting amine nitrogen and electron pulling iodine coordinate, and the formation of radical cation (polaron) structure in polymer chain (on amine nitrogen) is enabled [27].
Synthesized polymers shows deeper highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels with increased percentage of ID as electron pulling unit.
The protonated/deprotonated MUA ligand that caused changes in the dipole moment of molecules may trigger various degrees of electron pulling force (the carboxyl groups of MUA are electron-withdrawing groups[43]).
Judged by the HOF values, the 4- and 3-monosubstituted isomers are the most stable monosubstituted isomers when the electron pulling and pushing groups are attached to the pyrazole ring, respectively.
TTI as electron pushing unit and ID as electron pulling unit were incorporated in the push pull types of conjugated polymers (PTTIID, PTTIID-3, PTTIID-5 and PTTIID-7).
It is found that the molecular orientation of adsorption and the driving force for electron injection can be changed by the substitution of electron-pull moiety.
The adjustment of electron-donating and electron-withdrawing phenyl and pyridine substituted groups narrows the discrepancy of electron push-pull capabilities for dizao and coupling components, which makes possible the transformation for roles of donor and acceptor.
A series of N2,N6-bis 3-methoxypropyl pyridine-2,6-diamine azo dyes, prepared by coupliN2,N6-bis 3-methoxypropyl pyridine-2,6-diamineotiN2,N6-bis 3-methoxypropyl pyridine-2,6-diaminewith distiN2,N6-bis 3-methoxypropyl pyridine-2,6-diaminebeeN2,N6-bis 3-methoxypropyl pyridine-2,6-diamine
The positive electrons are pulled from the cathode through the emissive layer, which is then extracted by the anode through the conductive layer.
When discharged, electrons are pulled off the anode, fed through an external circuit where they do work, and returned to a second electrode called a cathode.
