Bulk heterojunction polymer

Liang YY, Xu Z, Xia JB, Tsai ST, Wu Y, Li G, Ray C, Yu LP (2010) For the bright future-bulk heterojunction polymer solar cells with power conversion efficiency of 7.4%. Adv Mater 22 E135... 

Fig. 17 Simple relationship of open circuit voltage Vqc for drift-current dominated bulk heterojunction polymer solar cells. The first limitation arises from the molecular energy levels (Voci) secondly, improper match with the contact work function may further reduce the achievable voltage to 002- (Reprinted with permission from [105], 2003, American Institute of Physics)...

Fig. 69 Ideal structure of a donor-acceptor bulk heterojunction polymer solar cell...

K. Maturova, M. Kemerink, M.M. Wienk, D.S.H. Charrier, and R.A.J. Janssen, Scanning Kelvin probe microscopy on bulk heterojunction polymer blends. Adv. Funct. Mater., 19, 1... 

Innovations in materials science and technology have provided promising strategies to realize a high photovoltaic performance. Besides the intrinsic properties of photoactive polymer materials, morphology is also critical in bulk heterojunction polymer solar cells. 

T. Hori, T. Masuda, N. Fukuoka, T. Hayashi, Y. Miyake, T. Kamikado, H. Yoshida, A. Fujii, Y. Shimizu, M. Ozaki, Non-peripheral octahexylphthalocyanine doping effects in bulk heterojunction polymer solar cells. Org. Electron. 13, 335-340 (2012)... 

D. Yu, K. Park, M. Durstock, L. Dai, Fullerene-Grafted Graphene for Efficient Bulk Heterojunction Polymer Photovoltaic Devices. J. Phys. Chem. Lett. 2011,2,1113-1118. 

Blankenburg, L., Schultheis, K., Schache, H., Sensfuss, S., and Schrodner, M. (2009) Reel-to-reel wet coating as an efficient up-scaling technique for the production of bulk-heterojunction polymer solar cells. Sol. Energy Mater. Sol. Cells, 93, 476-483. 

As a synthetic strategy, simple and versatile reactive blending will continue to play a pivotal role in the development of newer materials. For example, the blending technique is being used to produce bulk heterojunction polymer solar cells (polymer/fullerene) and to develop electrically conductive polymer blends using electrically conductive fillers and additives (Huang and Kipouras 2012). 

Wang C-L, Zhang W-B, Van Horn RM et al (2011) A potphyrin-fullerene dyad with a supramolecular double-cable structure as a novel electron acceptor for bulk heterojunction polymer solar cells. Adv Mater 23(26) 2951-2956... 

Scheme 3.8 Schematic illustration of the structure of a typical bulk heterojunction polymer solar cell device.

Lin C, Pan W-C, Tsai F-Y. Optimization of the active-layer morphology with a non-halogenic solvent for bulk-heterojunction polymer solar cells. Synth Met 2010 160(23-24) 2643-2647. 

Figure 4.1 (a) Device architecture of inverted bulk heterojunction polymer solar... 

Morphology of Bulk Heterojunction Polymer Solar Cells... 

The improvement in power conversion efficiency (PCE) of plasmonic solar cells is always an urgent problem and short circuit current density is one of the key factors for the PCE. The improvement in the Jsc of plasmonic solar cells is mainly achieved by the introduction of metallic nanoparticles, such as blending Au nanoparticles into the anodic buffer layer or the interconnecting layer that connects two subcells of the tandem plasmonic solar cells [86]. Compared with the metallic NPs, nanowires (NWs) are superior in terms of improving photocurrent, while most of the metallic NWs introducing in cells reported previously were used for the anodic contact of the cells [87]. The improvement of PCE in bulk heterojunction polymer solar cells with active layer P3HT PCBM by introducing 40 nm Au nanoparticles between ITO and PEDOT PSS layer with various concentrations is also observed by Gao et al. [88]. It has been found that both short-circuit current density and PCE increase from 3.50% to 3.81% with 0.9 wt. % Au NPs due to the localized surface plasmon excitation of Au NPs. 

C M. Liu, C M. Chen, Y.W. Su, S.M. Wang, K.H. Wei, The dual localized surface plasmonic effects of gold nanodots and gold nanoparticles enhance the performance of bulk heterojunction polymer solar cells, Org. Elect. 14 (2013) 2476-2483. 

Although multi-junction polymer solar cells are a valid strategy for reaching high PCEs, the increased number of layers that have to be processed on top of eaeh other increases the complexity of the fabrieation process. The first important factor is solvent orthogonality. Each of the layers has to be processed from a solution that will not damage or wash away any of the previously deposited layers. For processing on top of a bulk heterojunction polymer fullerene, only a few solvents can be used in praetiee water, aeetone, and alcohols. Typically, the photoactive layers are hydrophobie and this represents an obstacle to the deposition of materials from aqueous solutions because of poor wettability. Therefore, extra measures have to be taken such... 

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