Polymer photovoltaic cells

Yu, G., Gao, J., Hummelen, J.C., Wudl, F., and Heeger, A.J. (1995) Polymer photovoltaic cells enhanced efficiencies via a network of internal donor-acceptor heterojunctions. Science 270, 1789-1791. 

Liu Q, Liu Z, Zhang X et al (2009) Polymer photovoltaic cells based on solution-processable graphene and P3HT. Adv Funct Mater 19 894—904... 

It is indeed intriguing and very attractive to think of photovoltaic elements based on thin plastic films with low cost but large areas, cut from rolls and deployed on permanent structures and surfaces. In order to fulfil these requirements, cheap production technologies for large scale coating must be applied to a low cost material class. Polymer photovoltaic cells hold the potential of such low cost cells. Flexible chemical tailoring of desired properties, combined with the cheap technology already well developed for all kinds of plastic thin film applications, precisely fulfill the above-formulated demands for cheap photovoltaic device production. The mechanical flexibility of plastic materials is welcome for all photovoltaic applications onto curved surfaces in indoor as well as outdoor applications. 

In the case of thin devices, the transmittance may not be zero and the concept of IQE becomes less well defined. Most polymer photovoltaic cells are quite thin and only the photons absorbed in the active regions of the device can contribute to the photocurrent. The useful absorptance in the cells is given by... 

These novel properties are the basis for a number of application including polymer light emitting diodes (LEDs), polymer light-emitting electrochemical cells (LECs), conducting polymers as electrochromic materials, polymer photodetectors and polymer photovoltaic cells. These application areas are discussed in detail in Section VII. 

Since polymers can be deposited from solution, large area photocells can be made quite cheaply, on curved and even flexible substrates. This is particularly important for solar cells, which must be large to collect substantial amounts of solar energy. Unfortunately, polymer photovoltaic cells are not yet efficient enough for practical use. 

Li G., Shrotriya V., Huang J., Yao Y., Moriarty T., Emery K. and Yang Y., High-efficiency solution processable polymer photovoltaic cells by self-organization of polymer blends . Nature Materials 4, 864—868. 

Coakley KM, McGehee MD (2004) Conjugated polymer photovoltaic cells. Chem Mater 16 4533... 

Since the first report of the bulk heterojunction prototype (BHJ) of polymer photovoltaic cells [83], the power conversion efficiency (PCE) of this kind of photovoltaic cells has been much improved [84]. Further improvement of the power conversion efficiencies of BHJ devices needs systematic investigation of important... 

M.S. Kim, J.S. Kim, J.C. Cho, M. Shtein, LJ. Guo, and J. Kim, Flexible conjugated polymer photovoltaic cells with controlled heterojunctions fabricated using nanoimprint lithography, Appl. Phys. Lett., 90, 123113 (2007). 

Polymer photovoltaic cells are interesting not only for traditional applications, such as electric power generation, but also for large area, digital image sensing. ... 

A major disadvantage of polymer photovoltaic cells is the low photo-induced current, due to the low carrier mobility and short exciton migration distance. However, the electrical current for polymer photovoltaic cells can be significantly enhanced by adding a small amount of ionic solid electro-lyte. ... 

G. Li, V. Shrotriya, J. Huang, Y. Yao, T. Moriarty, K. Emery, Y. Yang, High-EfRciency Solution Processable Polymer Photovoltaic Cells by Self-Organization of Polymer Blends. Nat. Mater 2005,4,864-868. 

K. M. Coakley, M. D. McGehee, Conjugated Polymer Photovoltaic Cells. Chem. Mater. 2004,16,4533-4542. 

G. Yu, J. Gao, J. C. Hummelen, F. Wudl, A. J. Heeger, Polymer Photovoltaic Cells Enhanced Efficiencies via a Network of Internal Donor-Acceptor Heterojunctions. Science 1995,270,1789-1791. 

M.-S. Kim, J.-S. Kim, J. C. Cho, M. Shtein, L. J. Guo, J. Kim, Flexible Conjugated Polymer Photovoltaic Cells with Controlled Heterojunctions Fabricated Using Nanoimprint Lithography. Applied Physics Letters 2007, 90,123113. 

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