Polymer based solar cells

However, for relatively new types of solar cells such as the polymer-based solar cells described here, suitable stable reference cells cannot yet be fabricated. This implies that, for measurements concerning these cells, calibrated reference cells are used (Si, GaAs) with a different spectral response to the device under test, resulting in mismatch factors that deviate significantly from 1. It is therefore of the utmost importance to carry out the procedure as precisely as possible in order to minimise measurement errors. 

Fig.1 Structures of conjugated polymers and a soluble C o derivative commonly applied in polymer-based solar cells...

Apart from serving as substrate and conductive layer, polymers can be also used as functional layers in the fabrication of PSCs. An ultrathin and lightweight polymer-based solar cell with a thickness of less than 2 pm had been developed on a 1.4 pm-thick PET substrate (Fig. 9.1F). The resulting PSC showed a comparable power conversion efficiency of 4.2% with high flexibility. By adhering the flexible PSC to a prestretched elastomer, a stretchable PSC can be also fabricated. Even during repeated compression and stretching, these stretchable PSCs showed stable photovoltaic performances (Kaltenbrurmer etal., 2012). 

PAVs have emerged as one of the most important classes of conjugated polymers. Ironically, while their electrical properties, which were the original motivation for their study, have proved disappointing, their electro-optical properties are such that they comprise the active material in the first commercially available polymer-based LEDs, and they have been used in some of the best performing polymer-based solar cells yet tested. While considerable development remains before polymer-based electronic devices can represent more than a tiny share of the electronics market, there is every reason to believe that when they do, PAVs will form a significant fi action of the materials used. 

In turn, the realization of controlled placement of a SWCNT monolayer network at four different positions in polymer-C60 BHJ solar cells was demonstrated, and their optoelectronic performance was investigated. Several devices were fabricated by precisely placing SWCNTs at different hierarchical levels in the device with structure P3HT/PEDOT/ITO. Dip-coating from an additive-free suspension of mildly purified SWCNTs in DMF was utilized for this purpose. It was found that SWCNTs on the cathodic side of the active layer lead to increased PCE from 4 to 4.9% under AM 1.5 G illumination this being the highest value achieved for polymer-based solar cells incorporating CNTs [51]. 

P30T is a conducting LEP that finds use in OLED and PLED materials, FETs, and, probably most widely studied, polymer-based solar cells [116, 117]. Other alkyl substituted derivatives (particularly the regioregular 3-hexyl P3HT) are also widely used and are important materials for bulk heterojuncticm PV systems. 

Although polymer-based solar cells remain the most efficient devices constructed, small molecules such as organic semiconductors could represent a promising solar energy technology. - However, the weak point of these devices has always been the small efficiency in comparison with the levels obtained with polymeric cells. ... 

Mayer AC, Scully SR, Hardin BE, Rowell MW, McGehee MD (2007) Polymer-based solar cells. Mater Today 10 28-33... 

A. C. Mayer, et al.. Polymer-based solar cells. Materials Today, 10 (2007), 28... 

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