Molecular doping

In molecular doped polymers the variance of the disorder potential that follows from a plot of In p versus T 2 is typically 0.1 eV, comprising contributions from the interaction of a charge carrier with induced as well as with permanent dipoles [64-66]. In molecules that suffer a major structural relaxation after removal or addition of an electron, the polaron contribution to the activation energy has to be taken into account in addition to the (temperature-dependent) disorder effect. In the weak-field limit it gives rise to an extra Boltzmann factor in the expression for p(T). More generally, Marcus-type rates may have to be invoked for the elementary jump process [67]. 

There have been numerous studies of the electrical and emission properties of conjugated polymer-, small molecule-, and molecularly doped polymer-based OLEDs. The current-voltage and radiance-voltage characteristics have been nica sured as a function of thickness of the organic layer, temperature, different metal electrodes, etc. in an attempt to understand the device physics. A major factor in hibiting progress is the purity of the organic impurities that are incorporated dur-... 

In general, the solid surface in molecularly doped organic-inorganic silica gels participates actively in the reaction mechanism, by ... 

J Kido, M Kohda, K Okuyama, and K Nagai, Organic electroluminescent devices based on molecularly doped polymers, Appl. Phys. Lett., 61 761-763, 1992. 

Mattoussi H, Murata H, Merritt CD, Iizumi Y, Kido J, Kafafi ZH (1999) Photoluminescence quantum yield of pure and molecularly doped organic solid films. J Appl Phys 86 2642-2650... 

Dunlap DH, Parris PE, Kenkre VM (1996) Charge-dipole model for the universal field dependence of mobilities in molecularly doped polymers. Phys Rev Lett 77 542... 

Hirao A, Nishizawa H, Sugiuchi M (1995) Diffusion and drift of charge carriers in molecularly doped polymers. Phys Rev Lett 75 1787... 

Schein LB, Glatz D, Scott JC (1990) Observation of the transition from adiabatic to nonadiabatic small polaron hopping in a molecularly doped polymer. Phys Rev Lett 65 472... 

Schein LB, Tyutnev A (2008) The contribution of energetic disorder to charge transport in molecularly doped polymers. J Phys Chem C 112 7295... 

Borsenberger PM, Bassler H (1991) Concerning the role of dipolar disorder on charge transport in molecularly doped polymers. J Chem Phys 95 5327... 

Zhang Y, de Boer B, Blom PWM (2009) Controllable molecular doping and charge transport in solution-processed polymer semiconducting layers. Adv Funct Mater 19 1901... 

Rice MJ, Gartstein YN (1996) Theory of photoinduced charge transfer in a molecularly doped conjugated polymer. Phys Rev B 53 10764... 

Time-of-flight experiments have been used for over three decades to characterize carrier mobilities in crystal, and polycrystalline and disordered organic solids including molecularly doped polymers and molecular glasses [28,424,430,431]. Relatively high values (up to several hundreds cm2/V s) and hot carrier effects have been observed in... 

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