Modeling Current-Voltage Characteristics

The chapter is organized as follows. Section 1.2 reviews recent computational efforts focused on modeling current-voltage characteristics of functional dye-sensitized solar cells (DSSCs) under operational conditions, with emphasis on the effect of the nature of the molecular adsorbates and redox couple on the overall efficiency of photoconversion. Section 1.3 reviews recent developments of methods for inverse design of molecular adsorbers with suitable solar-light photoabsorption. Section 1.4 reviews the development of theoretical models of... 

However, although it allowed a correct description of the current-voltage characteristics, this model presents several inconsistencies. The main one concerns the mechanism of trap-free transport. As noted by Wu and Conwell [1191, the MTR model assumes a transport in delocalized levels, which is at variance with the low trap-free mobility found in 6T and DH6T (0.04 cm2 V-1 s l). Next, the estimated concentrations of traps are rather high as compared to the total density of molecules in the materials (see Table 14-4). Finally, recent measurements on single ciystals [15, 80, 81] show that the trap-free mobility of 6T could be at least ten times higher than that given in Table 14-4. 

The field sometimes called molecular electronics actually should extend well beyond simple measurement of current/voltage characteristics of single molecules. The latter topic, single molecule transport, has comprised by far the dominant reported molecular electronics measurement and modeling, and, as has been discussed above, the community is reaching some agreement in this area. 

Vilan A (2007) Analyzing molecular current-voltage characteristics with the Simmons tunneling model scaling and linearization. J Phys Chem C 111 4431-4444... 

Melikhov, E. and Gershanov, Y., Percolation Model of Ceramic High-Tc Superconductors. Critical Current and Current Voltage Characteristic, Physica Cl57 431 (1989). 

A simple analytical model of thermionic converter performance must be made before the impact of converter performance on system behavior can be studied. Fortunately, a very simple model of converter performance has been found to be sufficiently accurate for this purpose. The ideal thermionic diode serves as the basis for this model. Motive diagrams and converter current voltage characteristics for an ideal diode are shown in Figure 2. 

Phonon-assisted tunneling (PhAT) model has been shown to explain properly nonlinear current-voltage characteristics and temperature dependence of conductivity in carbon nanotubes and other nanostructures of organic materials [1,2], In this paper, we want to show that this model is workable in explanation of I-V characteristics of inorganic nanodevices (Bi xSbx)2Te3 nanowires measured in a wide temperature range, 1.75-350 K, by Xiao et al. [3] and ZnSnOs nanowires presented in [4]. 

As with all optoelectronic semiconductor devices, the current-voltage characteristics of an organic solar cell can be modelled using the continuity equations for each charge type. For electrons in the steady state we have... 

In contrast, SchUinsky et al. and Waldauf et al. used an extended numerical description according to the p-n jimction model and demonstrated as well a proper description of hght intensity-dependent device current-voltage characteristics [ 127,157,158]. Thus, several numerical models for the electrical description of polymer-fullerene photovoltaic devices have been presented in the literature to date, and there is an ongoing discussion in the scientific community about them. 

Barker JA, Ramsdale CM, Greenham NC (2003) Modeling the current-voltage characteristics of bilayer polymer photovoltaic devices. Phys Rev B 67 075205... 

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