Quantum dot-sensitized solar cells

Recombination in Quantum Dot Sensitized Solar Cells. Acc. Chem. Res. 2009,42 1848-1857. 

Chen, J. Lei, W. Zhang, X. B., Enhanced electron transfer rate for quantum dot sensitized solar cell based on CNT-Ti02 film./. Nanoscience andNanotechn. 2012,12 6476-6479. 

In this work, we present a brief introduction to the nonequilibrium Green s function method and discuss two important examples in which nonequli-brium Green s functions can be employed (1) electric current calculations in molecular tunneling devices and (2) in quantum dot-sensitized solar cells. 

Our interest in quantum dot-sensitized solar cells (QDSSC) is motivated by recent experiments in the Parkinson group (UW), where a two-electron transfer from excitonic states of a QD to a semiconductor was observed [32]. The main goal of this section is to understand a fundamental mechanism of electron transfer in solar cells. An electron transfer scheme in a QDSSC is illustrated in Figure 5.22. As discussed in introduction, quantum correlations play a crucial role in electron transfer. Thus, we briefly describe the theory [99] in which different correlation mechanisms such as e-ph and e-e interactions in a QD and e-ph interactions in a SM are considered. A time-dependent electric field of an arbitrary shape interacting with QD electrons is described in a dipole approximation. The interaction between a SM and a QD is presented in terms of the tunneling Hamiltonian, that is, in... 

Yu. Dahnovsky, Quantum correlated electron dynamics in a quantum-dot sensitized solar cell The Keldysh function approach, Phys. Rev. B (2011) (accepted). 

Fig. 19 Schematic depictions of (a) the preparation of a cobalt pyrite (C0S2) film electrode via the thermal sulfidation of a 100 nm thick cobalt film deposited over a titanium adhesion layer on a roughened borosilicate glass substrate by electron-beam evaporation and (b) the incorporation of an as-synthesized C0S2 film on glass into a CdS/ CdSe-sensitized thin-layer liquid-junction quantum dot-sensitized solar cell (QDSSC) filled with sulfide/polysulfide electrolyte to demonstrate the high QDSSC performance enabled by the C0S2 counter electrode. Reproduced from ref. 167 with permission from the American Chemical Society.

Figure 10.2 Principle of operation of liquid junction dye or quantum dot sensitized solar cell using mesoscopic Ti02 films.

Chang CH, Lee YL (2007) Chemical bath deposition of CdS quantum dots onto mesoscopic Ti02 films for application in quantum-dot-sensitized solar cells. Appl Phys Lett 91 053503-1-053503-3... 

Ruble S, Shalom M, Zaban A (2010) Quantum-dot-sensitized solar cells. Chem Phys Chem 11 2290-2304... 

Gonzalez-Pedro V, Xu X, Mora-Ser6 I, Bisquert J (2010) Modeling high-efficiency quantum dot sensitized solar cells. ACS Nano 10 5783-5790... 

Mali SS, Desai SK, Kalagi SS et al (2012) PbS quanmm dot sensitized anatase Ti02 nanocorals for quantum dot-sensitized solar cell applications. Dalton Trans 41 6130-6136... 

Mora-Soo I, Gimenez S, Fabregat-Santiago F, Granez R, Shen Q, Toyoda T, Bisquert J (2009) Recombination in quantum dot sensitized solar cells. Acc Chem Res 42 1848-1857... 

Lee, W, Kang, S.H., Kim, XY, Kolekar, G.B., Sung, YE. Han, S.H. Ti02 nanotubes with a ZnO thin energy barrier for improved current efficiency of CdSe quantum-dot-sensitized solar cells. Nanotechnology 20 33 (2009a), 335706. 

Lee, Y.L. Lo, Y.S. Highly efficient quantum-dot-sensitized solar cell based on co-sensitization of CdS/CdSe./lrfv. Funct. Mater. 19 4 (2009b), pp. 604-609. 

Ternary and quaternary materials based on copper chalcogenide nanomaterials have been developed as promising materials for sustainable energy production, due to their abundance and low toxicity. In addition to their use as light absorbers in solar cells, copper chalcogenide nanocrystals have also been used as electrode materials in Li-ion batteries and high efficiency counter electrodes in dye/quantum dot sensitized solar cells as well as for NIR photothermal therapy. 

Fig. 5 (a) Schematic illustration of the structure of a quantum dot sensitized solar cell (QDSC), and (b) schematic illustration of photo induced charge transfer processes following a laser pulse... 

P.K. Santra, P.V. Kamat, Mn-doped quantum dot sensitized solar cells a strategy to boost efficiency over 5%, J. Am. Chem. Soc. 134 (2012) 2508-2511. 

X-Y Yu, J-Y Liao, K-Q Qiu, D-B Kuang, C-Y Su, Dynamic study of highly efficient CdS/CdSe quantum dot-sensitized solar cells fabricated by electrodeposition, ACS Nano 5 (2011)9494-9500. 

G. Zhu, L. Pan, T. Xu, Z. Sun, CdS/CdSe-cosensitized Ti02 photoanode for quantum-dot-sensitized solar cells by a microwave-assisted chemical bath deposition method, ACS Appl. Mater. Inter. 3 (2011)3146-3151. 

B. Fang, M.-W. Kim, S.-Q. Fan, J.-H. Kim, D.P. Wilkinson, J.-J. Ko and J.-S. Yu, Facile synthesis of open mesoporous carbon nanofibers with tailored nanostructure as a highly efficient counter electrode in CdSe quantum-dot-sensitized solar cells, /. Mater. Chem. 21, 2011, 8742-8748. 

Q. Ma, H. Niu, S. Qin, X. Mao, R. Wang, L. Wan, and J. Xu, Preparation of CdSe Quantum Dot Sensitized Solar Cells Based on Improved Successive Ionic Layer Absorption and Reaction Method, J. Nanotnater. Molec. Nanotechnol, 2,1-7 ( 2013). 

Semiconductor NCs have been incorporated into solar cells in different configurations, for example (a) photoelectrodes composed of quantum dot arrays, (b) metal-semiconductor photovoltaic cells,(c) NC-polymer solar cells and (d) quantum dot sensitized solar cells. This field has been the focus of intense research in recent years because of the possibility that quantum dot-based solar cells can overcome the Shockley-Queisser photoconversion limit. This possibility relies on two feasible processes hot carrier extraction and multiple exciton generation (MEG). 

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