Hybrid Solar Cell

Plass R, Pelet S, Krueger J, Gratzel M, Bach U (2002) Quantum dot sensitization of organic-inorganic hybrid solar cells. J Phys Chem B 106 7578-7580... 

Lancelle-Beltran, E. Prene, P Boscher, C. Belleville, R Buvat, P Lambert, S. Guillet, F. Boissiere, C. Grosso, D. Sanchez, C. 2006. Nanostructured hybrid solar cells based on self-assembled mesoporous titania thin films. Chem. Mater. 18 6152-6156. 

Yin Z, Wu S, Zhou X et al (2010) Electrochemical deposition of ZnO nanorods on transparent reduced graphene oxide electrodes for hybrid solar cells. Small 6 307-312... 

Snaith H. J., Moule A. J., Klein C., Meerholz K., Friend R. H. and Gratzel M. (2007), Efficiency enhancements in solid-state hybrid solar cells via reduced charge recombination and increased light capture , Nano Letters 7, 3372-3376. 

Choi S.-H., Song H., Park 1. K., Yum J.-H., Kim S.-S., Lee S. and Snng Y.-E. (2006), Synthesis of size-controlled CdSe qnantum dots and characterization of CdSe-conjngated polymer blends for hybrid solar cells , J. Photochem. Photobiol. A 179, 135-141. 

Beek W. J. E., Wienk M. M. and Janssen R. A. J. (2004), Efficient hybrid solar cells from zinc oxide nanoparticles and a conjngated polymer , Adv. Mat. 16, 1009-1012. 

Kang Y. M., Park N. G. and Kim D. Y. (2005), Hybrid solar cells with vertically aligned CdTe nanorods and a conjugated polymer , Appl. Phys. Lett. 86, 113101-1 -113101-3. 

Fig. 56 ECE (A) of 7-, 30-, and 60-nm-long CdSe nanorods having a diameter of 7 nm. Current-voltage characteristics in the dark and O.lmW/cm (B) and at AM 1.5 solar spectrum (C) of P3HT CdSe hybrid solar cells. Photocurrent spectra of 60-nm-long nanorods with a diameter of 3 and 7 nm are compared in (D). From [250]. (Reprinted with permission from American Association for the Advancement of Science (AAAS), 2002. http //www.sciencemag.org)...

One extensively studied material system among the nanocrystal-polymer blends is zinc oxide (ZnO) in combination with MDMO-PPV or P3HT [273-282]. Beek et al. presented the first polymer solar cells containing ZnO nanoparticles, reaching power conversion efficiencies of 1.6% [273]. In this case the nanoparticles were prepared separately and then intermixed with MDMO-PPV in solution. Shortly after this study the Janssen group presented another route to ZnO-polymer hybrid solar cells by forming the nanocrystals in situ inside the film by applying a precursor [274]. Here, diethylzinc served as the precursor and was spin cast in blends with MDMO-PPV. Process-... 

Arid E, Sariciftci NS, Meissner D (2003) Hybrid solar cells based on nanoparticles of CuInS2 in organic matrices. Adv Funct Mater 13 165... 

Arid E, Hoppe H, Schaffler F, Meissner D, Malik MA, Sariciftci NS (2004) Hybrid solar cells based on inorganic nanoclusters and semiconductive polymers. Thin Solid Films 451-452 612... 

Gunes S, Neugebauer H, Sariciftci NS, Roither J, Kovalenko M, Pillwein G, Heiss W (2006) Hybrid solar cells using HgTe nanocrystals and nanoporous Ti02 electrodes. Adv Eunct Mater 16 1095... 

Beek WJE, Slooff LH, Wienk MM, Kroon JM, Janssen RAJ (2005) Hybrid solar cells using a zinc oxide precursor and a conjugated polymer. Adv Funct Mater 15 1703... 

Beek WJE, Wienk MM, Janssen RAJ (2006) Hybrid solar cells from regioregular polythiophene and ZnO nanopartides. Adv Funct Mater 16 1112... 

There are four different types of organic or organic/inorganic hybrid solar cells single-layer, bilayer, bulk heterojunction (BHJ), and dye-sensitized. The basic operation of each device type is described below. 

Ackermann, J. et ah. Highly efficient hybrid solar cells based on an octithiophene-GaAs heterojunction, A(7v. Eunct. Mater. 15, 810-817, 2005. 

Snaith, H.J., S.M. Zakeeruddin, L. Schmidt-Mende, C. Klein, and M. Gratzel, Ion-coordinating sensitizer in solid-state hybrid solar cells. Angewandte Chemie International Edition, 2005.44(39) pp. 6413-6417... 

In bulk (or dispersed) heterojunctions, nanocrystals are blended into the polymer to create a heterogeneous composite with a high interface surface area. In this hybrid solar cell concept, photo induced charge separation is favored between high electron affinity inorganic semiconductors and relatively low ionization potential polymer. The maximum power conversion efficiency has reached 2.8 % under AM 1.5 illumination condition by using the composite of tetrapods of CdSe nanocrystals and MDMO-PPV [4], while the PCE of the device based on the composite of CdTe nanorods and MEH-PPV is only 0.052 % in similar conditions [5]. 

Kwon, S., Shim, M., Lee, J.I., Lee, T.-W., Cho, K., Kim, J.K. Ultrahigh density array of CdSe nanorods for CdSe/polymer hybrid solar cells enhancement in short-circuit current density. J. Mato. Chem. 21, 12449 (2011)... 

H. J. Snaith, A. J. Moule, C. Klein, K. Meerholz, R. H. Friend, M. Gratzel, Efficiency Enhancements in Solid-State Hybrid Solar Cells via Reduced Charge Recombination and Increased Light Capture. Nano Lett. 2007, 7, 3372-3376. 

L. Zhao, Z. Lin, Crafting Semiconductor Organic-Inorganic Nanocomposites via Placing Conjugated Polymers in Intimate Contact with Nanocrystals for Hybrid Solar Cells. Adv. Mater. 2012,24,4353-4368. 

The above chemical coupling leads to uniform dispersion (as inferred from TEM images) of QCNs within CP matrix [162] leading to improved charge transfer/transport and enhancement of optoelectronic performance, e.g., light-to-electricity conversion efficiency in hybrid solar cells. 

Ihe Ught-to-electricity conversion efficiency or QE of hybrid solar cell is governed by the five basic steps involved in the process (Shown schematically in Figure 3.22) viz. light absorption by active material to form excitons (1), exciton diffusion toward interface (2), exciton dissociation at interface (3), free carriers (electron/hole) transport toward electrodes (4), and charge collection at respective electrodes (5) [178-180]. 

Figure 3.22 Schematic representation of the working of organic-inorganic bUayer hybrid solar cell showing different steps involved in conversion of photon to electricity.

State of the Art in Inorganic QCNs-Based Hybrid Solar Cells... 

Table 3.3 summarizes the performance parameters of the hybrid solar cells reported by different authors. 

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