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Carrier Collection

Harold J. Hovel, Introduction Carrier Collection, Spectral Response, and Photocurrent Solar Cell Electrical Characteristics Efficiency Thickness Other Solar Cell Devices Radiation Effects Temperature and Intensity Solar Cell Technology... [Pg.648]

The luminance reaches 100 cd/m2 at 2.5 V with EL efficiency of 2.5 cd/ A. The corresponding external quantum efficiency is about 2% ph/el. At —10 V bias, the photosensitivity at 430 nm is around 90 mA/W, corresponding to a quantum yield of 20% el/ph [135], The carrier collection efficiency at zero bias was relatively low in the order of 10-3 ph/el. The photosensitivity showed a field dependence with activation energy of 10 2 eV [135], This value is consistent with the trap distribution measured in the PPV-based conjugated polymers [136,137],... [Pg.19]

Having discussed the causes of pore wall passivity, we will now focus on the active state of the pore tip, which is caused by its efficiency in minority carrier collection. Usually the current density at the pore tip is determined by the applied bias. This is true for all highly doped as well as low doped p-type Si electrodes and so the pore growth rate increases with bias in these cases. For low doped, illuminated n-type electrodes, however, bias and current density become decoupled. The anodic bias applied during stable macropore formation in n-type substrates is... [Pg.186]

Fig. 10.4 (a) Computed minority carrier generation rate in bulk silicon for different wavelengths of monochromatic illumination of an intensity corresponding to a photocurrent density of 10 mA crrf2. (b) Bulk minority carrier density for carrier collection at the illumi-... [Pg.213]

Electrons and holes generated in the i-layer by incident light are driven to the n- and p-layer by the internal electric field, respectively. The material quality of the intrinsic layer and the strength and distribution of the electric field are responsible for the charge carrier collection and mainly determine the electrical solar cell performance. Defects affect the charge carrier collection in two different ways On the one hand they act as recombination centers, and on the other hand their charge state modifies the electric field distribution in the i-layer. [Pg.362]

If the thickness d of the absorber, nominally equal to the reciprocal absorption coefficient a-1, at optimised fractions d and d[(l — ) of the paths for electrons and holes to travel to the contacts, exceeds the combined diffusion length, a reasonable carrier collection can be achieved by spending the above drop in quasi-Fermi levels. [Pg.149]

Fig. 10.19. The dependence of the solar cell fill factor on the carrier collection length (Faughan and Crandall 1984). Fig. 10.19. The dependence of the solar cell fill factor on the carrier collection length (Faughan and Crandall 1984).
Light Absorption by the Semiconductor Electrode and Carrier Collection... [Pg.2679]

The number of carriers collected (in an external circuit, for example) versus those optically generated defines the quantum yield (C>), a parameter of considerable interest to photochemists. The difficulty here is to quantify the amount of light actually absorbed by the semiconductor since the cell walls, the electrolyte and other components of the assembly are all capable of either absorbing or scattering some of the incident light. Unfortunately, this problem has not been comprehensively tackled, unlike in the situation with photocatalytic reactors involving semiconductor particulate suspensions where such analyses are available [204-207]. Pending these, an effective quantum yield can still be defined. [Pg.2680]

Photoexcitation and Carrier Collection Steady-state Behavior... [Pg.2703]

The above result was obtained with front-side illumination geometry. As one would intuitively expect, carrier collection is most efficient close to the rear contact. Indeed, marked differences have been observed for photoaction spectra with the two irradiation (i.e., through the electrolyte side vs. through the transparent rear contact) geometries for Ti02, CdS and CdSe nanocrystalline films [319, 342]. Obviously, the relative magnitudes of the excitation wavelength and the film thickness critically enter into this variant behavior. [Pg.2705]

ATP is generated as a result of the energy produced when electrons from NADH and FADH2 are passed to molecular oxygen by a series of electron carriers, collectively known as the electron transport chain. The components of the chain includes FMN, Fe-S centers, coenzyme Q, and a series of cytochromes (b, cl5 c, and aa3). [Pg.116]

As material quality is inhomogeneous even after gettering and hydrogenation (Fig. 7.7), solar cell results are affected by both good and bad areas. Cell performance in areas of low diffusion length is limited due to recombination in the bulk, whereas rear surface recombination, 5b, can limit carrier collection in good quality areas. [Pg.112]

Dye-sensitized nanocrystalline cells are fundamentally different from the others discussed earlier in that they do not rely on semiconductor p-n junctions. Instead, they are electrochemical devices in which the optical absorption and carrier-collection processes are separated (Fig. 4). [Pg.2136]


See other pages where Carrier Collection is mentioned: [Pg.287]    [Pg.461]    [Pg.255]    [Pg.176]    [Pg.232]    [Pg.19]    [Pg.46]    [Pg.213]    [Pg.829]    [Pg.73]    [Pg.514]    [Pg.350]    [Pg.2680]    [Pg.2680]    [Pg.2684]    [Pg.2706]    [Pg.3563]    [Pg.514]    [Pg.10]    [Pg.49]    [Pg.394]   
See also in sourсe #XX -- [ Pg.306 ]




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Charge carrier collection

Nanostructures charge carrier collection

Photoexcitation and Carrier Collection Dynamic Behavior

Photoexcitation and Carrier Collection Steady-state Behavior

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