Bulk-heterojunction configuration

Fig. 3 Contemporary organic solar cell devices are based on donor/acceptor heterojunction device architectures, (a) Energy level diagram, (b) Planar heterojunction conligmation. (c) Bulk heterojunction configuration...

One of the most promising uses of C60 involves its potential application, when mixed with 7r-conjligated polymers, in polymer solar cells. Most often the so-called bulk heterojunction configuration is used, in which the active layer consists of a blend of electron-donating materials, for example, p-type conjugated polymers, and an electron-accepting material (n-type), such as (6,6)-phenyl-Cgi -butyric acid methyl ester (PCBM, Scheme 9.6).38... 

The bulk heterojunction material exhibits an ensemble of interface configurations, such that spectroscopic observables and measurable photocurrents reflect statistically averaged properties (with the exception of observations... 

FIGURE 2. Device configuration for heterojunction (a) and bulk-heterojunction (b) organic thin film solar cells. 

In a bulk-heterojunction photovoltaic cell with methanofullerene [6,6]-phenyl C61-butyric acid methyl ester (PCBM) as an electron acceptor, alternating copolymer 19 (Fig. 9), derived from 2,7-fluorene and 2,5-dithienylsilole, can show impressive performance as the electron donor.31 In a device configuration of ITO/PEDOT/active layer/Ba/Al, the dark current density—bias curve shows a small leakage current, suggesting a continuous, pinhole-free active layer in the device. Under illumination of an AM 1.5 solar simulator at 100 mW/cm2, a high short-circuit current of 5.4 mA/cm2, an open-circuit voltage of 0.7 V, and a fill factor of 31.5% are achieved. The calculated energy conversion efficiency is 2.01%. 

Figure 18.1 Structural configurations of typical solar cell made on glass substrate with transparent indium tin oxide (ITO) electrode. The active layer can typically have three configurations (1) single organic layer, (2) bilayer (double-layer) heterojunction between donor and acceptor and (3) bulk heterojunction...

Photovoltaic performance parameters of bulk heterojunction organic/polymer solar cell with NPs embedded in various configurations... 

Photovoltaic Performance Parameters of bulk Heterojunction Organic/Polymer Solar Cell with NPs Embedded in various Configurations... 

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